- dovecot - dovecot.org

Is this a bug of `doveadm mailbox metadata set` with `-A` and `-s ""`
by Zhang Huangbin 24 Apr '26

24 Apr '26

Dear all, Recently i encountered an issue with `doveadm mailbox metadata set` (and `unset`) with either `-A` or `-F <path>`. When i run `doveadm mailbox metadata set` for single user, it correctly generates content in `dovecot-attributes` file: ``` doveadm mailbox metadata set -u <email> -s "" "/private/vendor/vendor.dovecot/http-notify" "user=all" ``` But if i run with `-A`, or `-F <path>`, Dovecot generates incorrect "path" and unreadable characters in `dovecot-attributes` file: ``` # doveadm mailbox metadata set -A -s "" "/private/vendor/vendor.dovecot/http-notify" "user=all" # for i in $(find . -name 'dovecot-attributes'); do echo $i; cat $i; done priv/4898662293abe1690d9a000063130d18/vendor/vendor.dovecot/pvt/server/?????? user=all priv/90e7b40fc8c1e9690924000063130d18/vendor/vendor.dovecot/pvt/server/vendor/vendor.dovecot/http-notify user=all priv/60ba353790c1e969f923000063130d18/vendor/vendor.dovecot/pvt/server/endor.dovecot/pvt/server/CV?? user=all ``` It's ok if i specify the mailbox in -s, for example: `-s "INBOX"`, `-s "Sent"`, but it's not what i want, because only emails delivered to specified mailbox will be pushed. Is this a bug?

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[Bug Report] anvil panic: anvil-connection.c:727: unreached triggered by duplicate imap-login handshake with pid=-1
by Jeff Aitken 24 Apr '26

24 Apr '26

Environment: FreeBSD 14.4-RELEASE Dovecot 2.4.3 (e278b1e09b) Pigeonhole 2.4.3 (0bf9ee48) Postfix 3.11.1, rspamd 4.0.0 Description: The dovecot anvil process is crashing repeatedly with a panic in anvil-connection.c at line 727. The panic is triggered by i_unreached() in anvil_connection_destroy(). Total of ~18 crashes in the last 24 hours, happens to multiple users. The anvil process restarts successfully and works as expected other than the crashes. No other symptoms that I can see that appear related. Log messages: dovecot[87542]: anvil: Panic: file anvil-connection.c: line 727: unreached dovecot[87542]: anvil: Fatal: master: service(anvil): child 88408 killed with signal 6 (core not dumped) dovecot[87542]: anvil: Error: connect limit: disconnection for unknown (pid=88756, user=<username>, service=imap, ip=X.X.X.X, ...) dovecot[87542]: anvil: Warning: conn unix:anvil (uid=0): Handshake with duplicate service=imap-login pid=-1 - replacing the old connection Analysis (from claude): In anvil_connection_destroy(), when conn->added_to_hash is true, the code asserts that the connection must still be present in anvil_connections_hash. However, when a duplicate handshake is received for the same (service, pid) key, the old connection appears to be evicted from the hash table without clearing its added_to_hash flag. When the old connection is subsequently destroyed, hash_table_lookup_full() fails to find it, triggering i_unreached(). The pid=-1 in the duplicate handshake warning is also notable — this does not appear to be a valid process ID and may indicate that the handshake is being sent before the imap-login process has fully initialized. Workaround: Setting service_restart_request_count = unlimited and service_process_min_avail = 2 on the imap-login service seems to have reduces process turnover and appears to have reduced the frequency of the crash, but I’ve only got a couple of hours since that change so too early to say for sure. Suggested fix: When a duplicate handshake causes an existing connection to be evicted from anvil_connections_hash, the evicted connection's added_to_hash flag should be cleared to prevent the assertion failure in anvil_connection_destroy(). Appreciate any insight, and happy to provide additional info that would be helpful. —Jeff

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Unable to get Dovecot 2.4 to allow unencrypted connection
by David Koski 24 Apr '26

24 Apr '26

Hello, In spite of: ssl = no auth_allow_cleartext = yes ..in a telnet session, I get: * OK [CAPABILITY IMAP4rev1 SASL-IR LOGIN-REFERRALS ID ENABLE IDLE LITERAL+ STARTTLS LOGINDISABLED AUTH=GSSAPI AUTH=CRAM-MD5] Dovecot (Debian) ready. a1 login ln(a)zample.com <super-secret> * BAD [ALERT] Plaintext authentication not allowed without SSL/TLS, but your client did it anyway. If anyone was listening, the password was exposed. a1 NO [PRIVACYREQUIRED] Plaintext authentication disallowed on non-secure (SSL/TLS) connections. I need to see the network traffic to troubleshoot the way Outlook 2019 handles IMAP folders. Regards, David Koski dkoski(a)sutinen.com

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Re: large mbox files
by Joseph Tam 24 Apr '26

24 Apr '26

On Wed, 22 Apr 2026, Marc wrote: > How are messages deleted from large mbox files, are these files > completely rewritten? I can't really believe that as some are bigger > than the free disk space available. I think it's a little better than that: bytes are shuffled up to fill the deleted message hole. I gather this from noting the difference in operation time from deleting a message from the top vs bottom of a large mailbox. Joseph Tam <jtam.home(a)gmail.com>

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large mbox files
by Marc 23 Apr '26

23 Apr '26

How are messages deleted from large mbox files, are these files completely rewritten? I can't really believe that as some are bigger than the free disk space available.

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doveadm expunge silently ignores multiple -u flags instead of erroring or processing all users
by Robert Kretowicz 22 Apr '26

22 Apr '26

Hello, I would like to report what I believe is a bug in doveadm expunge argument handling. Summary When multiple -u flags are passed to doveadm expunge, for example: doveadm expunge -u user1 -u user2 -u user3 mailbox '*' BEFORE 2015-01-01 the command exits with code 0 (success) but only processes one of the specified users. The remaining users are silently skipped with no warning or error message produced. Why this is a bug This is a silent failure on a destructive, irreversible operation. An administrator has no indication that most users were not processed. Good CLI tools should either: Accept multiple -u flags and process all specified users (consistent with how -F file works), or Reject the command immediately with a clear error such as: Error: -u flag specified multiple times. Use -F <file> for multiple users. Silently accepting invalid input and doing something unpredictable is the worst possible outcome, especially for a mail expunge operation. Environment OS: Debian GNU/Linux 12 (Bookworm) Dovecot version: 2.3.x (from Debian package) doveconf -n output available on request — omitted due to containing internal domain names. Workaround I am currently using bashfor user in user1 user2 user3; do doveadm expunge -u "$user" mailbox '*' BEFORE 2015-01-01 done Thank you for your time. Robert Kretowicz

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Master user login attempted without master passdbs
by horst.simon.aus＠gmail.com 21 Apr '26

21 Apr '26

Hi, I have dovecot version v2.3.21.1 and my users (username(a)domain.name) are in mysql, all can logon to imap and sending mail, but when I am trying to create and enable sieve scripts from an weblient (horde webmail) it fails with authentication errors. It tries to use master user authentication and the logs are showing following: A pr 15 10:34:51 auth: Debug: client in: AUTH 1 PLAIN service=sieve secured session=yTdN4nRPFcF/AAAB lip=127.0.0.1 rip=127.0.0.1 lport=4190 rport=49429 resp=aG9yc3QAaG9yc3RAaGJzaW1vbi5uZXQAYXVnQDYmOXVzdA== (previous base64 data may contain sensitive data) Apr 15 10:34:51 auth: Info: plain(horst(a)hbsimon.net,127.0.0.1,<yTdN4nRPFcF/AAAB>): login user: Master user login attempted without master passdbs Apr 15 10:34:51 auth: Debug: auth(horst(a)hbsimon.net,127.0.0.1,<yTdN4nRPFcF/AAAB>): Auth request finished Apr 15 10:34:51 auth: Debug: auth client connected (pid=1478) Apr 15 10:34:53 auth: Debug: client passdb out: FAIL 1 user=horst(a)hbsimon.net Apr 15 10:34:53 managesieve-login: Info: Disconnected: Connection closed (auth failed, 1 attempts in 2 secs): user=<horst(a)hbsimon.net>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured, session=<yTdN4nRPFcF/AAAB> Apr 15 10:35:06 auth: Debug: client in: AUTH 1 PLAIN service=sieve secured session=VEgr43RPGMF/AAAB lip=127.0.0.1 rip=127.0.0.1 lport=4190 rport=49432 resp=aG9yc3QAaG9yc3RAaGJzaW1vbi5uZXQAYXVnQDYmOXVzdA== (previous base64 data may contain sensitive data) Apr 15 10:35:06 auth: Info: plain(horst(a)hbsimon.net,127.0.0.1,<VEgr43RPGMF/AAAB>): login user: Master user login attempted without master passdbs Apr 15 10:35:06 auth: Debug: auth(horst(a)hbsimon.net,127.0.0.1,<VEgr43RPGMF/AAAB>): Auth request finished Apr 15 10:35:06 auth: Debug: auth client connected (pid=1484) Apr 15 10:35:08 auth: Debug: client passdb out: FAIL 1 user=horst(a)hbsimon.net Apr 15 10:35:08 managesieve-login: Info: Disconnected: Connection closed (auth failed, 1 attempts in 2 secs): user=<horst(a)hbsimon.net>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured, session=<VEgr43RPGMF/AAAB> How can I bypass the master user login and use the assigned user or what should the master user be and how to create it? Thanks and Regards, Horst

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Dovecot 2.4 SETQUOTA, how to allow (admin) users to set quota (and write it back to LDAP)
by Johannes Nohl 21 Apr '26

21 Apr '26

Is it true that Dovecot dismissed the functionality of SETQUOTA with version 2.4.0 - without any replacement? see https://dovecot.org/mailman3/archives/list/dovecot-news@dovecot.org/message… Does this also applies to 2.4.2 and 2.4.3, or does the mechanism of plugin imap_quota returned (manual reads that there are no options to this plugin)? IMAP always replies `c008 NO [NOPERM] Permission denied (0.001 + 0.000 secs).` If you can activate the former `quota_set` option, how to combine it with LDAP? I know that you can read Quota from LDAP with userdb field `quota_storage_size = {ldap:quotaBytes}B`. But how to set it? I also remember an old opinion that writing LDAP is to slow, you should store quota e.g. in a text file and write it back to LDAP time shifted. That would be fine for me - however, how to enable SETQUOTA then? Thank you for help. -- Johannes Nohl postmaster(a)i-t-cloud.de

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Config: Reading value from file for password does not work
by René Neumann 19 Apr '26

19 Apr '26

Hi, I want to read the ldap auth-dn password from a file to avoid having it as part of the configuration (which may be checked into VCS). I specified ldap_auth_dn_password = </some/file where /some/file contains the password without extra whitespace (esp. there is no `\n`, I checked with xxd). But ldap auth does not succeed because of a wrong password. Password itself does work though, as checked with ldapsearch (even using the same file as password provider) `doveconf -x -P` *does* show the correct value. The same issue has been reported back in 2019 [1], without any reply though :-/ Any ideas? Thanks, René [1] https://dovecot.org/list/dovecot/2019-September/117100.html

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[Bug Report] 2.4.3 on macOS: anvil panics at anvil-connection.c:727 on every IMAP client handshake
by I-K-D-T＠web.de 19 Apr '26

19 Apr '26

Hi Dovecot developers, I'm hitting a reproducible anvil panic on macOS when any IMAP client tries to connect. Every client handshake triggers an `i_unreached()` assertion in `anvil-connection.c:727`, causing the anvil child to be killed with SIGABRT. Dovecot keeps restarting anvil, but every subsequent connection attempt triggers the same panic, so the service effectively cannot accept logins. ## Environment - Dovecot: 2.4.3 (e278b1e09b), Pigeonhole 2.4.3 (0bf9ee48) -- from Homebrew - OS: macOS 15.6 (Sequoia, Darwin 24.6.0, arm64/Apple Silicon, APFS) - Mail client: Mozilla Thunderbird 149.0.2 - Dovecot started via `sudo brew services start dovecot` (launchd) ## Reproducing 1. Fresh macOS install of Dovecot 2.4.3 via Homebrew. 2. Configure a minimal single-user IMAP setup with `passdb static` / `userdb static`, SSL on port 993 with a self-signed cert, Maildir storage (config at end of this mail). 3. Start Dovecot as root via launchd (`sudo brew services start dovecot`). 4. Connect any IMAP client to localhost:993 (I used Thunderbird 149 with a permanent cert exception for the self-signed certificate). 5. The client hangs / reports "server closed the connection" / sees no folders. 6. `dovecot.log` fills with repeated entries like the following: ``` anvil: Warning: conn unix:anvil (uid=0): Handshake with duplicate service=imap-login pid=-1 - replacing the old connection anvil: Panic: file anvil-connection.c: line 727: unreached anvil: Error: Raw backtrace: 0 libdovecot.0.dylib backtrace_append + 72 -> 1 libdovecot.0.dylib backtrace_get + 44 -> 2 libdovecot.0.dylib default_fatal_finish + 72 -> 3 libdovecot.0.dylib default_error_handler -> 4 libdovecot.0.dylib i_internal_error_handler -> 5 libdovecot.0.dylib i_fatal -> 6 libdovecot.0.dylib default_write -> 7 anvil anvil_connection_input_line -> 8 libdovecot.0.dylib connection_input_read_stream + 196 -> 9 libdovecot.0.dylib connection_input_default + 72 -> 10 libdovecot.0.dylib io_loop_call_io + 116 -> 11 libdovecot.0.dylib io_loop_handler_run_internal + 284 -> 12 libdovecot.0.dylib io_loop_handler_run + 220 -> 13 libdovecot.0.dylib io_loop_run + 88 -> 14 libdovecot.0.dylib master_service_run + 292 -> 15 anvil main + 368 -> 16 dyld start + 6076 anvil: Fatal: master: service(anvil): child NNNN killed with signal 6 (core dumps disabled) ``` The key signature is the two-line sequence: ``` Warning: conn unix:anvil (uid=0): Handshake with duplicate service=imap-login pid=-1 - replacing the old connection Panic: file anvil-connection.c: line 727: unreached ``` Every IMAP client handshake produces this. The `pid=-1` in the handshake warning looks suspicious -- it appears anvil is either not receiving a valid pid from imap-login or is registering a second connection with the same service name before the first is cleaned up. ## Workarounds attempted (none succeeded) - User-level setup with default_login_user=andreas -> same panic - Root-level setup with default_login_user=andreas -> same panic - Root-level setup with default_login_user=_www (unprivileged macOS service account with uid=70) -> same panic - Adding `default_vsz_limit = unlimited` (required separately on macOS because setrlimit(RLIMIT_DATA) fails with EINVAL on Darwin) -> did not affect anvil - Plaintext IMAP on 143 (no TLS) vs. IMAPS on 993 with self-signed cert -> same panic in both - Restarting Dovecot via launchd (`sudo brew services stop/start dovecot`) -> the panic recurs on the next connection ## `doveconf -n` output ``` # 2.4.3 (e278b1e09b): /opt/homebrew/etc/dovecot/dovecot.conf # Pigeonhole version 2.4.3 (0bf9ee48) # OS: Darwin 24.6.0 arm64 apfs # Hostname: macbook-air-von-andreas.local dovecot_config_version = 2.4.3 auth_mechanisms = plain login default_internal_group = _www default_internal_user = _www default_login_user = _www default_vsz_limit = unlimited dovecot_storage_version = 2.4.3 info_log_path = /opt/homebrew/var/log/dovecot/dovecot-info.log listen = 127.0.0.1 log_path = /opt/homebrew/var/log/dovecot/dovecot.log mail_driver = maildir mail_gid = staff mail_home = /Users/andreas/mail/%{user} mail_path = /Users/andreas/mail/%{user} mail_uid = andreas protocols = imap ssl_server { cert_file = /opt/homebrew/etc/dovecot/ssl/dovecot.crt key_file = /opt/homebrew/etc/dovecot/ssl/dovecot.key } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } } passdb static { password = # hidden } userdb static { fields { gid = staff home = /Users/andreas/mail/%{user} uid = andreas } } namespace inbox { mailbox_list_layout = fs inbox = yes prefix = separator = / } ``` ## What I would expect The anvil connection from imap-login should register with a valid pid (not -1) or anvil should tolerate the re-registration gracefully instead of hitting an i_unreached() assertion. ## Note on `dovecot-sysreport` Running `dovecot-sysreport` as the normal user fails with permission errors on `/opt/homebrew/var/run/dovecot/*` sockets (log-errors, master). The `grep -P` usage inside the script also fails on BSD grep (macOS). Let me know if a sysreport archive would be useful -- I can re-run with sudo and adjust grep if needed. Happy to provide further reproduction details, additional log output, or test any fix suggestions. Thanks for Dovecot. Andreas Marth I-K-D-T(a)web.de

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imap-sieve, question concerning "sieve_user_email" and variables, migration from 2.3 to 2.4
by Claus-Justus Heine 18 Apr '26

18 Apr '26

Hi there, I have a question concerning the configuration setting sieve_user_email In a v2.3 setup I had it set to sieve_user_email = %Ln(a)some.concrete.domain Now I am trying to migrate to v2.4 and thought the direct translation from the old variable expansion scheme to the new scheme deployed in v2.4 would be sieve_user_email = %{user|username|lower}(a)some.concrete.domain However, this does not work. Testing the documentation yields the following error: # dovecot -n -c dovecot.conf > /dev/null doveconf: Error: sieve: sieve settings: Failed to parse configuration: Failed to expand sieve_user_email setting variables: Unknown variable 'user' doveconf: Fatal: Error in configuration file dovecot.conf: Failed to initialize Sieve Setting "sieve_user_email" to something without variable expansion or just commenting it out yields a configuration which is accepted by "dovecot -n". Now I wonder: a) v2.3 did not complain. But perhaps just because it was using "%Ln" literally? b) In case it did work in v2.3, should it work in v2.4 also? And if so: what would be the correct syntax / variable names? c) Under which circumstances is this setting "sieve_user_email" used? The documentation states: https://doc.dovecot.org/main/core/summaries/settings.html#sieve_user_email > The primary e-mail address for the user. > > This is used as a default when no other appropriate address is available for sending messages. > > If this setting is not configured, either the postmaster or null <> address is used as a sender, depending on the action involved. > > This setting is important when there is no message envelope to extract addresses from, such as when the script is executed in IMAP. I thought that then it would make sense to use something which depends on the login-name of the IMAP-user? Or was this "sieve_user_email" intended to hold just one static email like "my_global_catch_all(a)some.concrete.domain"? Kind thanks for clarification, best regards Claus -- Claus-Justus Heine himself(a)claus-justus-heine.de http://www.claus-justus-heine.de/ Schatzmeister der Camerata Academica Freiburg e.V. --- www.cafev.de

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still a compile error in 2.4.3
by matthias 14 Apr '26

14 Apr '26

Hi, I got this message while I compile the version 2.4.3: libtool: error: cannot find the library '../../src/lib-lua/libdovecot-lua.la' or unhandled argument '../../src/lib-lua/libdovecot-lua.la' Thanks Matthias

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INBOX.dovecot.sieve not selectable
by 87auteur-niobium＠icloud.com 14 Apr '26

14 Apr '26

Hi folks, I’m seeing “INBOX.dovecot.sieve” listed on the response of the IMAP LIST command, but attempting to select the mailbox fails with “Internal server error occurred. Refer to the server log for more information”. I assume INBOX.dovecot.sieve is an internal/system folder that shouldn’t be on the LIST response. Is this a known issue? If it is, is it being tracked anywhere (I don’t see an “Issues” tab on GitHub for Dovecot Core)?

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imap-login not passing DSN through
by Hadmut Danisch 14 Apr '26

14 Apr '26

Hi, I have a problem with postfix + dovecot 1:2.3.21+dfsg1-2ubuntu6.3 on Ubuntu Server 24.04: When using dovecot's imap-login to verify users and passwords againgst dovecot's user list, it doesn't pass the DSN flag through, therefore effectively disabling DSN. Postfix, submission port bound to 127.0.0.1, port 587: 250-myhostname 250-PIPELINING 250-SIZE 18432000 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250-DSN 250-SMTPUTF8 250 CHUNKING but imap-login (configured to forward to 127.0.0.1:587): 250-myhostname 250-8BITMIME 250-AUTH PLAIN 250-BURL imap 250-CHUNKING 250-ENHANCEDSTATUSCODES 250-SIZE 250 PIPELINING So both the size limit and DSN are not passed through, SMTPUTF8 either. Even setting imap_capability = +DSN in 20-imap.conf doesn't help. What is keeping dovecot's imap-login from offering DSN? best regards Hadmut Hi, I have a problem with postfix + dovecot 1:2.3.21+dfsg1-2ubuntu6.3 on Ubuntu Server 24.04: When using dovecot's imap-login to verify users and passwords againgst dovecot's user list, it doesn't pass the DSN flag through, therefore effectively disabling DSN. Postfix, submission port bound to 127.0.0.1, port 587: 250-myhostname 250-PIPELINING 250-SIZE 18432000 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250-DSN 250-SMTPUTF8 250 CHUNKING but imap-login (configured to forward to 127.0.0.1:587): 250-myhostname 250-8BITMIME 250-AUTH PLAIN 250-BURL imap 250-CHUNKING 250-ENHANCEDSTATUSCODES 250-SIZE 250 PIPELINING So both the size limit and DSN are not passed through, SMTPUTF8 either. Even setting imap_capability = +DSN in 20-imap.conf doesn't help. What is keeping dovecot's imap-login from offering DSN? best regards Hadmut

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doveadm batch crash
by Jonathan Casiot 13 Apr '26

13 Apr '26

Hi I'm having an issue with doveadm batch - the following command always crashes: doveadm batch : mailbox status all inbox Whereas the following work as expected: doveadm mailbox status all inbox doveadm batch : mailbox list Any assistance gratefully received. Debug output from the crash: Debug: Loading modules from directory: /usr/lib64/dovecot Debug: Module loaded: /usr/lib64/dovecot/lib01_acl_plugin.so Debug: Module loaded: /usr/lib64/dovecot/lib10_mail_crypt_plugin.so Debug: Module loaded: /usr/lib64/dovecot/lib90_stats_plugin.so Debug: Loading modules from directory: /usr/lib64/dovecot/doveadm Debug: Module loaded: /usr/lib64/dovecot/doveadm/lib10_doveadm_acl_plugin.so Debug: Skipping module doveadm_expire_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib10_doveadm_expire_plugin.so: undefined symbol: expire_set_deinit (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_quota_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib10_doveadm_quota_plugin.so: undefined symbol: quota_user_module (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_fts_lucene_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib20_doveadm_fts_lucene_plugin.so: undefined symbol: lucene_index_iter_deinit (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_fts_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib20_doveadm_fts_plugin.so: undefined symbol: fts_user_get_language_list (this is usually intentional, so just ignore this message) Debug: Module loaded: /usr/lib64/dovecot/doveadm/libdoveadm_mail_crypt_plugin.so doveadm(jc): Debug: Effective uid=1001, gid=100, home=/home/jc doveadm(jc): Debug: acl: No acl_shared_dict setting - shared mailbox listing is disabled doveadm(jc): Debug: mail_crypt_plugin: mail_crypt_curve setting missing - generating EC keys disabled doveadm(jc): Debug: Namespace inbox: type=private, prefix=, sep=., inbox=yes, hidden=no, list=yes, subscriptions=yes location=mdbox:~/mdbox:ALT=~/Archive/tape/mdbox doveadm(jc): Debug: fs: root=/home/jc/mdbox, index=, indexpvt=, control=, inbox=, alt=/home/jc/Archive/tape/mdbox doveadm(jc): Debug: acl: initializing backend with data: vfile doveadm(jc): Debug: acl: acl username = jc doveadm(jc): Debug: acl: owner = 1 doveadm(jc): Debug: acl vfile: Global ACLs disabled doveadm(jc): Panic: file mail-storage.c: line 875 (mailbox_set_reason): assertion failed: (reason != NULL) doveadm(jc): Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0xa0e9e) [0x7fc993023e9e] -> /usr/lib64/dovecot/libdovecot.so.0(default_fatal_handler+0x2a) [0x7fc993023f0a] -> /usr/lib64/dovecot/libdovecot.so.0(i_fatal+0) [0x7fc992fb3c97] -> /usr/lib64/dovecot/libdovecot-storage.so.0(+0x49856) [0x7fc993301856] -> /usr/bin/doveadm(+0x348e2) [0x5631dbb5f8e2] -> /usr/bin/doveadm(+0x2e1ad) [0x5631dbb591ad] -> /usr/bin/doveadm(+0x2bd2c) [0x5631dbb56d2c] -> /usr/bin/doveadm(+0x2c92a) [0x5631dbb5792a] -> /usr/bin/doveadm(doveadm_mail_try_run+0x215) [0x5631dbb58285] -> /usr/bin/doveadm(main+0x46a) [0x5631dbb473fa] -> /lib64/libc.so.6(__libc_start_main+0xf5) [0x7fc992bd83d5] -> /usr/bin/doveadm(+0x1c565) [0x5631dbb47565] Aborted (core dumped) And doveconf -n output: # 2.2.36 (1f10bfa63): /etc/dovecot/dovecot.conf # OS: Linux 3.10.0-957.1.3.el7.x86_64 x86_64 CentOS Linux release 7.6.1810 (Core) # Hostname: ### redacted ### first_valid_gid = 100 first_valid_uid = 1000 last_valid_gid = 100 last_valid_uid = 1999 listen = * login_greeting = IMAP ready login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e session=<%{session}> %k mail_attribute_dict = file:%h/mdbox/dovecot-attributes mail_location = mdbox:~/mdbox:ALT=~/Archive/tape/mdbox mail_plugins = acl stats mail_crypt mailbox_list_index = yes mdbox_rotate_size = 16 M namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = separator = . } passdb { driver = pam } plugin { acl = vfile mail_crypt_global_private_key = <### redacted ### mail_crypt_global_public_key = <### redacted ### mail_crypt_save_version = 2 stats_memory_limit = 16 M stats_refresh = 30 secs stats_track_cmds = yes } postmaster_address = ### redacted ### protocols = imap service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } service imap-login { process_limit = 200 process_min_avail = 4 service_count = 1 } service stats { fifo_listener stats-mail { group = users mode = 01224 } } ssl = required ssl_cert = <### redacted ### ssl_key = # hidden, use -P to show it ssl_prefer_server_ciphers = yes ssl_protocols = !SSLv2 !SSLv3 !TLSv1 userdb { driver = passwd } verbose_proctitle = yes protocol imap { imap_idle_notify_interval = 10 mins imap_metadata = yes mail_max_userip_connections = 20 mail_plugins = acl stats mail_crypt imap_acl imap_stats } Regards, -- Jonathan

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decode2text
by Joan Moreau 13 Apr '26

13 Apr '26

Hi I can't find decode2text.sh in the git Where is it maintained ? Thank you Joan Hi I can't find decode2text.sh in the git Where is it maintained ? Thank you Joan

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Fwd: [EXT] In Yocto-Mailinglist, there were two version of dovecot 2.4.3 found?
by Martin Maurer 10 Apr '26

10 Apr '26

Hello, resent to get clarification, about different content of 2.4.3 release tar file Best regards, Martin -------- Weitergeleitete Nachricht -------- Betreff: Re: [EXT] In Yocto-Mailinglist, there were two version of dovecot 2.4.3 found? Datum: Fri, 10 Apr 2026 14:37:36 +0300 (EEST) Von: Aki Tuomi <aki.tuomi(a)open-xchange.com> An: Martin Maurer <martin.maurer(a)mmeacs.de> Kopie (CC): dovecot-owner(a)dovecot.org <dovecot-owner(a)dovecot.org> Please send mails to dovecot(a)dovecot.org, which is our public mailing list. Aki > On 10/04/2026 14:18 EEST Martin Maurer <martin.maurer(a)mmeacs.de> wrote: > > Hi, > > in Yocto mailing list there was found out, that two different version > of dovecot 2.4.3 seems to exist: > > > https://github.com/dovecot/core/releases/download/2.4.3/dovecot-2.4.3.tar.gz > > > sha256:e0b30330fe51e47ecfcf641bc16041184d91bdd0ac3db789b7cef54e3a75ac9b > > > https://dovecot.org/releases/2.4/dovecot-2.4.3.tar.gz > > SHA256: ff0be85228122f250627b19e67505fdb7fb2f72a702ef6bf35f27fce54c072e5 > > > When downloading both and comparing them: > > The doc/man directory seem to be different. > > When I had looked correctly, all others files seems to be identical. > > > Can you explain, what could have happened? > > In Yocto the SHA256 checksum is checked, and this seems to fail, when > the one or the other download place is used. > > Is this as planned or had an error happened? > > > Many thanks for the clarification! > > > Best regards, > > Martin Hello, resent to get clarification, about different content of 2.4.3 release tar file Best regards, Martin -------- Weitergeleitete Nachricht -------- Betreff: Re: [EXT] In Yocto-Mailinglist, there were two version of dovecot 2.4.3 found? Datum: Fri, 10 Apr 2026 14:37:36 +0300 (EEST) Von: Aki Tuomi [1]<aki.tuomi(a)open-xchange.com> An: Martin Maurer [2]<martin.maurer(a)mmeacs.de> Kopie (CC): [3]dovecot-owner(a)dovecot.org [4]<dovecot-owner(a)dovecot.org> Please send mails to [5]dovecot(a)dovecot.org, which is our public mailing list. Aki On 10/04/2026 14:18 EEST Martin Maurer [6]<martin.maurer(a)mmeacs.de> wrote: Hi, in Yocto mailing list there was found out, that two different version of dovecot 2.4.3 seems to exist: [7]https://github.com/dovecot/core/releases/download/2.4.3/dovecot-2.4.3.tar… sha256:e0b30330fe51e47ecfcf641bc16041184d91bdd0ac3db789b7cef54e3a75ac9b [8]https://dovecot.org/releases/2.4/dovecot-2.4.3.tar.gz SHA256: ff0be85228122f250627b19e67505fdb7fb2f72a702ef6bf35f27fce54c072e5 When downloading both and comparing them: The doc/man directory seem to be different. When I had looked correctly, all others files seems to be identical. Can you explain, what could have happened? In Yocto the SHA256 checksum is checked, and this seems to fail, when the one or the other download place is used. Is this as planned or had an error happened? Many thanks for the clarification! Best regards, Martin References Visible links 1. mailto:aki.tuomi@open-xchange.com 2. mailto:martin.maurer@mmeacs.de 3. mailto:dovecot-owner@dovecot.org 4. mailto:dovecot-owner@dovecot.org 5. mailto:dovecot@dovecot.org 6. mailto:martin.maurer@mmeacs.de 7. https://github.com/dovecot/core/releases/download/2.4.3/dovecot-2.4.3.tar.gz 8. https://dovecot.org/releases/2.4/dovecot-2.4.3.tar.gz

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Source tarballs for dovecot 2.4.3 republished
by Aki Tuomi 10 Apr '26

10 Apr '26

Hi! We have republished the source tarballs for 2.4.3 due to missing man pages in the tarball. Regards, AKi

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Dovecot Proxy with mysql passdb and oauth2 authentication: upgrade from 2.3.21 to 2.4.3 does not work
by Urban Loesch 07 Apr '26

07 Apr '26

Hi, I am running a Dovecot IMAP/POP3 proxy in my test environment using the latest version, 2.3.21, installed from the Dovecot repository. It functions as a pure IMAP/POP3 proxy for 7 different IMAP backends (currently always Dovecot 2.3.21). The proxy retrieves all its information from a MySQL database mainly the ip-address to which backend he should pass the connection and forwards all authentication information to the backend. This has always worked without any issues so far. Now I'm trying to upgrade the proxy from 2.3.21 to 2.4.3. I tried to convert my 2.3.21 configuration to 2.4.3 with your very helpfull tool from https://dovecot.org/upgrader/. But now when I try to start dovecot I get the followong error in my logs: ... 2026-04-07T12:00:57.692994+02:00 imap-dev dovecot: auth: Debug: Loading modules from directory: /usr/lib/dovecot/modules/auth 2026-04-07T12:00:57.695908+02:00 imap-dev dovecot: auth: Debug: Module loaded: /usr/lib/dovecot/modules/auth/libdriver_mysql.so 2026-04-07T12:00:57.696532+02:00 imap-dev dovecot: auth: Fatal: Cannot initialize oauth2: Missing oauth2_introspection_mode setting 2026-04-07T12:00:57.697569+02:00 imap-dev dovecot: master: Error: service(auth): command startup failed, throttling for 4.000 secs ... As I just said, the server only works as a proxy (no mailboxes hosted on itself, etc). Have you any idea how I can solve this issues? Below my current .deb packages installed and "doveconf -n" from 2.4.3. Many thanks in advance Urban ----------------------- # dpkg -l |grep dovecot ii dovecot-core 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - core files ii dovecot-imapd 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - IMAP daemon ii dovecot-ldap 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - LDAP support ii dovecot-lmtpd 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - LMTP server ii dovecot-managesieved 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - ManageSieve server ii dovecot-mysql 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - MySQL support ii dovecot-pop3d 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - POP3 daemon ii dovecot-sieve 2:2.4.3-1+debian12 amd64 secure POP3/IMAP server - Sieve filters support ------------------------ # 2.4.3-1+debian12 (c1b22ef978): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.3-1+debian12 (99939e07) # OS: Linux 6.1.0-31-amd64 x86_64 Debian 12.13 # Hostname: imap-dev.domain.com dovecot_config_version = 2.4.3 auth_cache_negative_ttl = 0 auth_cache_size = 128 M auth_cache_ttl = 0 auth_debug = yes auth_debug_passwords = yes auth_failure_delay = 5 secs auth_mechanisms = plain login oauthbearer xoauth2 auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_%@ auth_username_translation = %@ dovecot_storage_version = 2.4.0 login_log_format_elements = user=<%{user}> method=%{mechanism} rip=%{remote_ip} lip=%{local_ip} mpid=%{mail_pid} %{secured} %{ssl_security} managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext protocols = imap sieve sql_driver = mysql ssl_min_protocol = TLSv1 verbose_proctitle = yes namespace inbox { inbox = yes mailbox Drafts { special_use = "\\Drafts" } mailbox Junk { special_use = "\\Junk" } mailbox Sent { special_use = "\\Sent" } mailbox "Sent Messages" { special_use = "\\Sent" } mailbox Trash { special_use = "\\Trash" } } passdb sql { default_password_scheme = PLAIN query = SELECT NULL AS password, 'y' AS nodb, SUBSTRING_INDEX(SUBSTRING_INDEX(param, '[', -1), ']', 1) AS host, '%{user}' AS destuser, 'Y' AS nologin, 'Y' AS nopassword, 'Y' AS proxy, '%{mechanism}' AS proxy_mech FROM mail_username WHERE user = '%{user}' AND allow_login = 'y' AND ('%{protocol}' = 'imap' OR '%{protocol}' = 'sieve'); } mysql devdb1.domain.com { dbname = mailconfig_dev password = # hidden, use -P to show it user = imap-dev } sieve_script personal { driver = file path = ~/sieve } service imap-login { process_min_avail = 2 restart_request_count = unlimited vsz_limit = 512 M } service managesieve-login { inet_listener sieve { port = 4190 } } service pop3-login { process_min_avail = 2 restart_request_count = unlimited vsz_limit = 256 M } service tcpwrap { unix_listener login/tcpwrap { group = $SET:default_login_user mode = 0600 user = $SET:default_login_user } } ssl_server { cert_file = /etc/letsencrypt/live/domain.com/fullchain.pem dh_file = /etc/dovecot/dh.pem key_file = /etc/letsencrypt/live/domain.com/privkey.pem prefer_ciphers = server } protocol imap { imap_capability = IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE login_greeting = Domain-Dev IMAP Server ready. } protocol pop3 { login_greeting = Domain-Dev POP3 Server ready. pop3_enable_last = yes pop3_uidl_format = %{uid | substr(0, 8)}%{uidvalidity | substr(0, 8)} }

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Dovecot and Pigeonhole v2.4.3 released
by Aki Tuomi 07 Apr '26

07 Apr '26

Hi! We are happy to publish version 2.4.3 of Dovecot and Pigeonhole. These contain several CVEs, discovered by external researches. The majority of these have been discovered with help of automated code analysis tools like claude code security, which is why some of these are rather old, missed bugs. No new supported distros have been added or old removed, no new dependencies have been added. Note that there are experimental features in 2.4, one is enabled with `--enable-experimental-mail-utf8`, and another with `--enable-experimental-imap4rev2`, and you also need to set mail_utf8_extensions=yes and imap4rev2_enabled=yes to enable them in config. https://dovecot.org/releases/2.4/dovecot-2.4.3.tar.gz https://dovecot.org/releases/2.4/dovecot-2.4.3.tar.gz.sig https://pigeonhole.dovecot.org/releases/2.4/dovecot-pigeonhole-2.4.3.tar.gz https://pigeonhole.dovecot.org/releases/2.4/dovecot-pigeonhole-2.4.3.tar.gz… Binary packages in https://repo.dovecot.org/ Docker images in https://hub.docker.com/r/dovecot/dovecot --- * CVE-2025-59028: Invalid base64 authentication can cause DoS for other logins. * CVE-2025-59031: decode2text.sh OOXML extraction may follow symlinks and read unintended files during indexing. Fixed by dropping the script. * CVE-2026-24031: SQL injection possible if auth_username_chars is configured empty. Fixed escaping to always happen. v2.4 regression. * CVE-2026-27859: Excessive RFC 2231 MIME parameters in email would cause excessive CPU usage. Fixed by limiting number of parameters to process. * CVE-2026-27860: LDAP query injection possible if auth_username_chars is configured empty. Fixed escaping to always happen. v2.4 regression. * CVE-2026-27857: Sending excessive parenthesis causes imap-login to use excessive memory. * CVE-2026-27856: Doveadm credentials were not checked using timing-safe checking function. * CVE-2026-27855: OTP driver vulnerable to replay attack. * Remove default service/*/service_extra_groups=$SET:default_internal_group. They are now replaced by default mail_access_groups=$SET:default_internal_group. * The version file has been renamed as version.txt to avoid clash with C++ headers. * auth: oauth2 - Do not export token automatically, must be exported using fields. * config: Don't accept 0 as meaning unlimited anymore for last_valid_uid, last_valid_gid, mail_cache_max_headers_count, mail_cache_max_header_name_length, mail_vsize_bg_after_count, mail_sort_max_read_count, message_max_size, submission_max_recipients and quota_mail_size. * imap, pop3: Don't autoexpunge if Dovecot is shutting down or process is killed. * imap: LIST - Handle invalid mUTF-7 mailbox names as never matching anything * lazy-expunge: Change lazy_expunge_only_last_instance default to yes. * lda: Use EX_TEMPFAIL (75) if configuration is invalid instead of 89. v2.4 regression. * lib-master: Increase ANVIL_DEFAULT_LOOKUP_TIMEOUT_MSECS from 5s to 30s * lib: crc32 - Use zlib's built-in CRC32 function + Improve UTF-8 support for mail storage. + auth: Add default auth-token UNIX socket for token-based authentication. + doc: solr-config-9.xml - Make it compatible with Solr 9.8.0 + doveadm: dsync - Search mails when exporting to reduce number of mails exported by dsync-server. + dovecot-sysreport: Add -D|--destdir support. + imap, imap-hibernate: Use DOVECOT-TOKEN authentication for unhibernation. Default imap-master socket permissioms have been changed due to this. + imap: Add APPENDLIMIT capability when configured with quota_mail_size. + imap: Support STATUS (DELETED) for IMAP4rev2. + imapc: Add support for SEARCH MIMEPART + imapc: Improve error forwarding. + imapc: Support SORT and ESORT extensions. + imapc: Support STATUS (DELETED) for IMAP4rev2. + lib-sql: Support parameterized queries. + lib-test: Add new test-dir API for better temporary test directory handling. + lmtp: Advertize SIZE capability when configured with quota_mail_size. + lmtp: Support XCLIENT DESTADDR and DESTPORT + pop3-login: proxy - Add support for XCLIENT DESTIP and DESTPORT + submission-login: proxy - Add support for XCLIENT DESTIP and DESTPORT + Various optimizations have been made to the code. - Fix building dovecot with BSD, Solaris and macOS. - auth: Crash would occur if users were iterated but userdb_ldap_iterate_fields was not set. - auth: Fix request leak when client authenticates with unsupported mechanism. - auth: Some passdbs would default to PLAIN instead of CRYPT scheme. - config: Section and setting names could have been intermixed, resulting in the setting being silently ignored. - configure: Fix checking if BUILD_IMAP_HIBERNATE is set - doveadm: dsync - -e parameter was handled wrong with dsync-server. - fts-flatcurve: Mailbox leak would occur if mailbox failed to open. - imap: Fix potential issues with unhibernation and process state handling. - imapc: SEARCH failure handling was done wrong. - imapc: UID STORE commands included extra comma in uidset. - lib-auth-client: auth-master - Fix panic when reconnecting after handshake timeout. - lib-compression: Lz4 algorithm would assert-crash with malicious data. - lib-dcrypt: Fix digest algorithm handling. - lib-dict: Escape username paths to prevent traversal issues with dict-fs. - lib-http: Fix HTTP parsing edge cases and state handling. - lib-iostream: Disallow empty ssl_min_protocol. - lib-json: Fix incorrect character handling logic. - lib-ldap: Fix various TLS related bugs. - lib-mail: Fix charset translation and MIME parsing edge cases. - lib-mail: Fix multiple bounds checks and parsing issues in message handling. - lib-var-expand: Multiple fixes and improvements for expansion handling. - lib: Fix punycode decoding out-of-bounds reads. - lib: Fix unicode normalization edge cases causing crashes. - lib-http: Chunked transfer trailer size was not limited. - login-common: Improve logging and internal error handling. - login-common: login_log_format_elements was split by spaces naively, which could break variable expansion. Use template aware splitting now. - master: Dovecot would fail to start if listen directive was used and dovenull or dovecot user was missing. - pop3c: Connection might've hung with SSL. - util: Fix handling of environment variables containing control characters. - Many other bugs have been fixed. --- * CVE-2026-27858: managesieve-login can allocate large amount of memory during authentication. * CVE-2025-59032: ManageSieve panic occurs with sieve-connect as a client. * lib-sieve: Don't accept 0 as meaning unlimited anymore for sieve_quota_script_count and sieve_quota_storage_size. * managesieve-login: If mail_max_userip_connections is reached, return LIMIT/CONNECTIONS resp-code. * managesieve-login: proxy - Return unexpected backend failures as TRYLATER/NORETRY resp-code. * managesieve: Remove default service_extra_groups=$SET:default_internal_group. + managesieve-login: proxy - Add support for XCLIENT DESTIP and DESTPORT. - imapsieve: Fix panic occurring upon implicit flag changes. - lib-sieve: include-extension - Fix crash occurring when previous global command has no arguments. - lib-sieve: Fix erroneous attempt to read active script for non-personal storage. - lib-sieve: ldap: Fix linking non-shared LIBDOVECOT.

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Bug report: filter `default` in LDAP context does not suppress error logging
by Johannes Nohl 07 Apr '26

07 Apr '26

Bug report: Expanding variables with filter `default` in LDAP context does not suppress error logging if LDAP attribute is missing. Expected behaviour: Missing LDAP attribute does not throw an error. Example `nologin = %{ldap:missingAttribute | default}` Details: Please note: The missing attribute is called `shadowInactive` in reality. There might be another issue, the field nologin is boolean and set true if any value is assigned -- while default without parameter returns empty (thus, you cannot use default with nologin without workaround). The intended behaviour is documented clearly, however due to a bug in rendering you need to look into the doc sources (my PR for that was accepted already: https://doc.dovecot.org/2.4.2/core/config/auth/databases/ldap.html#ldap-spe… https://github.com/dovecot/documentation/pull/1478#pullrequestreview-403461… Full context: passdb ldap { driver = ldap ldap_filter = (&(objectClass=posixAccount)(mail=%{user})) fields { user = %{ldap:uid} nologin = %{ldap:shadowInactive | default} reason = The account for this email address is disabled. } } The same error was reported already a year ago, although among others, see point 4: https://dovecot.org/mailman3/archives/list/dovecot@dovecot.org/thread/TLJ2O… Please excuse my first attempt of 31-03-2026. It was unreadable. Aki already tried to help but was - I guess - distracted from the main point. I found a workaround for the missing attribute translation to boolean fields (if someone is interested) https://dovecot.org/mailman3/archives/list/dovecot@dovecot.org/thread/67Z4C… I tested with dovecot 2.4.2 and 2.4.3 (openSUSE repos) against local LDAP. The check for disabled users throws permanently errors in the log file, whenever the user is missing the ldap attribute for disabled. Thus, for each login of all enabled users (you will probably agree that this not acceptable). This results in the following log line: 2026-03-31T00:46:31.102690+02:00 mailserver dovecot: auth(test,ipv4,sasl:plain)<YE81n0VOVuofEeSD>: Error: ldap: auth_passdb_post settings: Failed to parse configuration: Failed to expand passdb_fields/nologin setting variables: ldap: No such attribute 'shadowinactive' Thank you Johannes -- Johannes Nohl postmaster(a)i-t-cloud.de

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[Dovecot] migration from IMAP/POP3 courier server to a remote dovecot server
by nik600 06 Apr '26

06 Apr '26

Dear all i'm planning a transparent migration from a courier server that provides both IMAP and POP3 access to users to a remote dovecot server with both IMAP and POP3 access. I have to migrate about 2500 users for 250 GB of space. I'm using dovecot 2.2.5.4 on debian6 squeeze. To make a transparent migration i have to maintain old IMAP UIDs and POP3 UIDs, so i've read http://wiki2.dovecot.org/Migration and http://wiki2.dovecot.org/Migration/Courier and http://wiki2.dovecot.org/Migration/Dsync And decided that probably the best tool to use is Dsync, as the courier-dovecot-migrate.pl<http://www.dovecot.org/tools/courier-dovecot-migrate.pl> script works only locally. I've tested the dsync following instructions reported above but after the migration of one test-account the client re-download messages. If i want to keep both IMAP UIDs and POP3 UIDs i have to sync both imapc and pop3c with two commands? doveadm -o imapc_user=foo -o pop3c_user=foo -o imapc_password=bar -o pop3c_password=bar backup -R -u user@domain imapc: doveadm -o imapc_user=foo -o pop3c_user=foo -o imapc_password=bar -o pop3c_password=bar backup -R -u user@domain pop3c: Or imapc is enough? Do you have any suggestion? Thanks -- /*************/ nik600 http://www.kumbe.it

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oath-toolkit pam authentication with dovecot
by "Tóth Attila" 04 Apr '26

04 Apr '26

Anybody has experience in deploying oath-toolkit totp authentication for dovecot? It works for ssh in a challenge response fashion, but I have concernes against concatenating the password with the totp digits, because I have difficulties even with su+oath_toolkit... Thx: Dw. -- dr Tóth Attila, Radiológus, 06-20-825-8057 Attila Toth MD, Radiologist, +36-20-825-8057

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enabling fts_flatcurve on debian
by Stefan G. Weichinger 03 Apr '26

03 Apr '26

Which xapian-related packages do I need? I have issues enabling the plugin ... pls advise

2 6

2.4 upgrade : INBOX does not exist
by Stefan G. Weichinger 03 Apr '26

03 Apr '26

Today I upgraded a server at a customer. I modified the config I had built over the last week, with the help of this list. So far nearly everything works, but thunderbird complains about non-existing mailboxes like INBOX. But we can access it, it's a bit strange. In the filesystem it looks like: # ls -la /home/vmail/our.tld/user\(a)our.tld/ insgesamt 7096 drwx------ 69 vmail vmail 4096 2. Apr 19:00 . drwx------ 129 vmail vmail 12288 2. Apr 18:56 .. drwx------ 5 vmail vmail 4096 8. Jun 2021 .Administrator drwx------ 5 vmail vmail 4096 2. Apr 18:40 .Administrator.Archiv drwx------ 5 vmail vmail 4096 2. Apr 18:40 '.Administrator.Domainwechsel AquaCC' drwx------ 5 vmail vmail 4096 11. Mai 2025 .Archives drwx------ 5 vmail vmail 4096 2. Apr 18:40 .Archives.2001 drwx------ 5 vmail vmail 4096 2. Apr 18:40 .Archives.2002 drwx------ 5 vmail vmail 4096 2. Apr 18:40 .Archives.2003 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2004 drwx------ 5 vmail vmail 4096 2. Apr 18:40 .Archives.2005 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2006 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2007 drwx------ 5 vmail vmail 4096 10. Feb 18:17 .Archives.2008 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2009 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2010 drwx------ 5 vmail vmail 4096 10. Feb 18:10 .Archives.2011 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2012 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2013 drwx------ 5 vmail vmail 4096 10. Feb 18:09 .Archives.2014 drwx------ 5 vmail vmail 4096 12. Aug 2024 .Archives.2015 drwx------ 5 vmail vmail 4096 2. Apr 17:51 .Archives.2016 drwx------ 5 vmail vmail 4096 11. Feb 11:57 .Archives.2017 drwx------ 5 vmail vmail 4096 10. Jun 2025 .Archives.2018 drwx------ 5 vmail vmail 4096 11. Feb 11:57 .Archives.2019 drwx------ 5 vmail vmail 4096 10. Feb 18:23 .Archives.2020 drwx------ 5 vmail vmail 4096 1. Apr 20:18 .Archives.2021 drwx------ 5 vmail vmail 4096 30. Mär 09:37 .Archives.2022 drwx------ 5 vmail vmail 4096 1. Apr 20:18 .Archives.2023 drwx------ 5 vmail vmail 4096 1. Apr 20:18 .Archives.2024 drwx------ 5 vmail vmail 4096 2. Apr 17:48 .Archives.2025 drwx------ 5 vmail vmail 4096 2. Apr 17:59 .Archives.2026 drwx------ 2 vmail vmail 323584 2. Apr 19:00 cur -rw------- 1 vmail vmail 0 2. Aug 2021 dovecot-acl-list -rw------- 1 vmail vmail 70712 2. Apr 18:37 dovecot.index -rw------- 1 vmail vmail 6266860 2. Apr 19:01 dovecot.index.cache -rw------- 1 vmail vmail 32160 2. Apr 19:00 dovecot.index.log -rw------- 1 vmail vmail 46940 2. Apr 06:20 dovecot.index.log.2 -rw------- 1 vmail vmail 91 18. Aug 2020 dovecot-keywords -rw------- 1 vmail vmail 65 2. Apr 18:37 .dovecot.lda-dupes drwx------ 5 vmail vmail 4096 2. Apr 18:37 .dovecot.lda-dupes.locks -rw------- 1 vmail vmail 6504 2. Apr 18:49 dovecot.list.index -rw------- 1 vmail vmail 3356 2. Apr 19:02 dovecot.list.index.log -rw------- 1 vmail vmail 2904 7. Jän 13:53 dovecot.mailbox.log -rw------- 1 vmail vmail 186894 2. Apr 18:59 dovecot-uidlist -rw------- 1 vmail vmail 8 7. Jän 13:53 dovecot-uidvalidity -r--r--r-- 1 vmail vmail 0 21. Apr 2020 dovecot-uidvalidity.5e9efc52 drwx------ 5 vmail vmail 4096 2. Apr 12:02 .Drafts drwx------ 5 vmail vmail 4096 12. Jun 2025 '.Entw&APw-rfe' drwx------ 5 vmail vmail 4096 6. Mai 2020 .Gesendet drwx------ 5 vmail vmail 4096 2. Apr 18:22 .INBOX.Administrator drwx------ 5 vmail vmail 4096 2. Apr 18:21 .INBOX.Alerts [..] We have mail_home = /home/vmail/%{user | domain}/%{user} I tried mail_home = /home/vmail/%{user | domain}/%{user | username} but that breaks things completely. In 2.3 we had these namespaces: namespace { type = private separator = / prefix = #location defaults to mail_location. inbox = yes } namespace { type = public separator = / prefix = Oeffentlich/ location = maildir:/home/vmail/oeffentlich subscriptions = yes } I tried "prefix = INBOX/" ... not good. I share the config, a little bit anonymized, acls removed ... # doveconf -n # 2.4.1-4 (7d8c0e5759): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.1-4 (0a86619f) # OS: Linux 6.12.74+deb13+1-amd64 x86_64 Debian 13.4 # Hostname: xxxx dovecot_config_version = 2.4.1 auth_allow_weak_schemes = yes auth_cache_size = 4M auth_debug = yes auth_mechanisms = plain login auth_verbose = yes default_process_limit = 300 dovecot_storage_version = 2.4.0 import_environment { CORE_ERROR = %{env:CORE_ERROR} CORE_OUTOFMEM = %{env:CORE_OUTOFMEM} LISTEN_FDS = %{env:LISTEN_FDS} LISTEN_PID = %{env:LISTEN_PID} MALLOC_MMAP_THRESHOLD_ = 131072 NOTIFY_SOCKET = %{env:NOTIFY_SOCKET} PATH = %{env:PATH} TZ = :/etc/localtime } info_log_path = /var/log/dovecot.info listen = * [::] log_path = /var/log/dovecot.log mail_debug = yes mail_driver = maildir mail_gid = 5000 mail_home = /home/vmail/%{user | domain}/%{user} mail_path = ~ mail_plugins { acl = yes notify = yes quota = no } mail_uid = 5000 protocols = imap sieve lmtp sieve_extensions { fileinto = yes reject = yes envelope = yes encoded-character = yes vacation = yes subaddress = yes comparator-i;ascii-numeric = yes relational = yes regex = yes imap4flags = yes copy = yes include = yes body = yes variables = yes enotify = yes environment = yes mailbox = yes date = yes index = yes ihave = yes duplicate = yes mime = yes foreverypart = yes extracttext = yes editheader = yes mboxmetadata = yes servermetadata = yes spamtest = yes spamtestplus = yes virustest = yes } sieve_global_extensions { vnd.dovecot.debug = yes vnd.dovecot.environment = yes vnd.dovecot.pipe = yes } sieve_pipe_bin_dir = /usr/lib/dovecot/sieve sieve_plugins = sieve_imapsieve sieve_extprograms sieve_spamtest_score_max_value = 15 sieve_spamtest_status_header = X-Spamd-Result: .*? \[([[:digit:]]+\.[[:digit:]]+) / [[:digit:]]+\.[[:digit:]]+\]; sql_driver = mysql ssl = required verbose_proctitle = yes mysql /var/run/mysqld/mysqld.sock { dbname = postfix_db password = # hidden, use -P to show it user = postfix_user } passdb sql { default_password_scheme = MD5-CRYPT query = SELECT username as user, password FROM mailbox WHERE ((username = '%{user | username}(a)domain1.at') OR (username = '%{user | username}(a)domain2.at')) AND active = '1' } userdb sql { iterate_query = SELECT userid AS username, domain FROM users query = SELECT username as user FROM mailbox WHERE ((username = '%{user | username}(a)domain1.at') OR (username = '%{user | username}(a)domain2.at') ) AND active = '1' } namespace inbox { inbox = yes prefix = separator = / type = private } namespace oeffentlich { mail_path = /home/vmail/oeffentlich prefix = Oeffentlich/ separator = / subscriptions = yes type = public mailbox Oeffentlich { acl [DELETED for now] } service imap-login { process_min_avail = 8 inet_listener imap { port = 0 ssl = no listen = } inet_listener imaps { port = 993 ssl = yes listen = } } service lmtp { extra_groups = $SET:default_internal_group user = vmail unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0660 user = postfix } } service imap { } service auth { client_limit = 1200 user = root unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-client { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { mode = 0660 } } service auth-worker { } service dict { unix_listener dict { } } ssl_server { cert_file = /etc/letsencrypt/pfsense/cloud_imap_mail_smtp_LE_cert.fullchain key_file = /etc/letsencrypt/pfsense/cloud_imap_mail_smtp_LE_cert.key } protocol lda { mail_plugins = sieve } protocol imap { imap_idle_notify_interval = 29 mins mail_max_userip_connections = 50 mail_plugins { imap_acl = yes imap_quota = no imap_sieve = yes } } protocol lmtp { mail_plugins = sieve postmaster_address = logs(a)xunil.at } service managesieve-login { inet_listener sieve { port = 4190 } } service managesieve { } protocol sieve { managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave } sieve_script personal { active_path = /home/vmail/%{user | domain}/%{user}/sieve/scripts/.dovecot.sieve driver = file path = /home/vmail/%{user | domain}/%{user}/sieve/scripts } sieve_script before-0 { driver = file path = /usr/lib/dovecot/sieve/global-spam.sieve type = before } service anvil { unix_listener anvil { group = $SET:default_internal_group mode = 0660 } } I assume I am not far from full success, I'd just like to get rid of these errors because tomorrow dozens of users will access their mailboxes ... Thanks for any pointers!

1 1

BUG-Report: mysql: SSL support not compiled in (remove ssl_client_ca_file and ssl_client_ca_dir settings) third attempt!
by Klaus Tachtler 02 Apr '26

02 Apr '26

Hello everyone, Problem info: ============ An error occurs, while trying to establish a TLS/SSL secured connection to a database (mariadb), which has the ability to accept TLS/SSL connections. Analysis from Archlinux Gitlab Issue, which could be found under following link by - Toolybird: https://gitlab.archlinux.org/archlinux/packaging/packages/dovecot/-/issues/… > Thanks for reporting. It would appear to be some kind of (upstream?) > bug in the autofoo. The error message can be traced back to > HAVE_MYSQL_SSL being undefined when it should be defined. This is > reflected in log: https://reproducible.archlinux.org/api/v0/builds/946041/log > It took quite some debugging, but adding the following hack before the > autoreconf call appears to make it work: > checking for mysql_ssl_set in -llibmariadb... no > sed -i 's/mysql_driver="libmariadb"/mysql_driver="mariadb"/' m4/ > want_mysql.m4 > After that it now shows: > checking for mysql_ssl_set in -lmariadb... yes Steps to reproduce: ================== 1. Configure dovecot 2.4.2-4 as described below 2. Restart dovecot 2.4.2-4 3. Try send an email (echo "Test-E-Mail" | /usr/sbin/sendmail root) 4. Determine error messages inside dovecot 2.4.2-4-Log > 01 Dec 22 04:57:38 server dovecot[842]: auth: Error: > mysql(db.idmz.tachtler.net): mysql: SSL support not compiled in > (remove ssl_client_ca_file and ssl_client_ca_dir settings) > 02 Dec 22 04:57:38 server dovecot[842]: auth-worker: Error: > mysql(db.idmz.tachtler.net): mysql: SSL support not compiled in > (remove ssl_client_ca_file and ssl_client_ca_dir settings) Additional info: =============== OS version: Archlinux package version(s): dovecot 2.4.2-4 necessary config file part: > 45 sql_driver = mysql > 46 > 47 mysql db.idmz.tachtler.net { > 48 host = db.idmz.tachtler.net > 49 port = 3306 > 50 user = postfixuser > 51 password = secret > 52 dbname = postfix > 53 ssl = yes > 54 ssl_client_ca_file = /etc/dovecot/ssl/certs/CAcert.pem > 55 ssl_client_cert_file = > /etc/dovecot/ssl/certs/client.idmz.tachtler.net.pem > 56 ssl_client_key_file = > /etc/dovecot/ssl/private/client.idmz.tachtler.net.key.pem > 57 ssl_cipher_list = DHE-RSA-AES256-SHA > 58 } WITHOUT the following line, a database connections is possible and works as expected: > 53 ssl = yes > 54 ssl_client_ca_file = /etc/dovecot/ssl/certs/CAcert.pem > 55 ssl_client_cert_file = > /etc/dovecot/ssl/certs/client.idmz.tachtler.net.pem > 56 ssl_client_key_file = > /etc/dovecot/ssl/private/client.idmz.tachtler.net.key.pem > 57 ssl_cipher_list = DHE-RSA-AES256-SHA Thanky you in advance for your help! Klaus Tachtler. -- --------------------------------------- e-Mail : klaus(a)tachtler.net Homepage: https://www.tachtler.net DokuWiki: https://dokuwiki.tachtler.net ---------------------------------------

3 17

Error: sieve: fail2ban: line 23: read(<lmtp DATA local>) failed: Seeking past EOF by 2364 bytes
by Graham Cobb 02 Apr '26

02 Apr '26

Hi, dovecot is crashing for me while doing sieve processing for messages received via lmtp. This is reproducible, and seems to hit every message which runs a particular sieve script. Any thoughts or help would be appreciated! The error is: Error: sieve: fail2ban: line 23: read(<lmtp DATA local>) failed: Seeking past EOF by 2364 bytes Note: the number of bytes is always one of: 2169, 2272, 2259, 2364. I have many of these. I cannot see how the "Seeking past EOF" error can be caused by a bug in my sieve script. But please let me know if it can! Background: I have (and have had for many years) a complex set of sieve scripts for controlling my incoming email. They have worked fine for all that time. However, recently (ish), processing which uses a particular script is crashing dovecot. The actual log extract is below. The sieve script line 23, mentioned in the error report, is a large "if anyof (" statement containing many clauses like: body :raw :regex "country:[[:space:]]+KR", I can provide the full sieve script if required. This is what I see in the dovecot log (note: I reformatted the backtrace to make it easier to read. I also changed all my server names): Mar 29 03:03:52 SERVER dovecot-HOST: lmtp(4008073): Connect from local Mar 29 03:03:52 SERVER dovecot-HOST: lmtp(cobb)<4008073><PiAQHoiIyGmJKD0Ay7SJiA>: Error: sieve: fail2ban: line 23: read(<lmtp DATA local>) failed: Seeking past EOF by 2364 bytes Mar 29 03:03:52 SERVER dovecot-HOST: lmtp(cobb)<4008073><PiAQHoiIyGmJKD0Ay7SJiA>: Error: sieve: Execution of script 'auto:personal/.dovecot' was aborted due to temporary failure (user logfile /home/cobb/.dovecot.sieve.log may reveal additional details) Mar 29 03:03:52 SERVER dovecot-HOST: lmtp(cobb)<4008073><PiAQHoiIyGmJKD0Ay7SJiA>: Panic: file istream-concat.c: line 27 (i_stream_concat_close): assertion failed: (cstream->cur_input == cstream->input[cstream->cur_idx]) Mar 29 03:03:52 SERVER dovecot-HOST: lmtp(cobb)<4008073><PiAQHoiIyGmJKD0Ay7SJiA>: Error: Raw backtrace: #1 [unw_get_proc_name() failed: -10] -> #2 [unw_get_proc_name() failed: -10] -> #3 i_panic[0x7f41540655e6] -> #4 [unw_get_proc_name() failed: -10] -> #5 io_stream_unref[0x7f415413c120] -> #6 i_stream_unref[0x7f4154145c30] -> #7 index_storage_mailbox_close[0x7f4154383e70] -> #8 mailbox_close[0x7f41542fd9e0] -> #9 mailbox_free[0x7f4154302ab0] -> #10 lmtp_local_deinit[0x55dfa9c4e320] -> #11 client_state_reset[0x55dfa9c4f0d0] -> #12 smtp_server_transaction_free[0x7f4154091880] -> #13 smtp_server_connection_reset_state[0x7f4154093c90] -> #14 smtp_server_command_call_hooks[0x7f415408be60] -> #15 smtp_server_command_send_replies[0x7f4154090050] -> #16 [unw_get_proc_name() failed: -10] -> #17 [unw_get_proc_name() failed: -10] -> #18 io_loop_call_io[0x7f4154151710] -> #19 io_loop_handler_run_internal[0x7f41541534b0] -> #20 io_loop_handler_run[0x7f4154153640] -> #21 io_loop_run[0x7f4154153820] -> #22 master_service_run[0x7f41540a6330] -> #23 main[0x55dfa9c4a260] -> #24 __libc_start_call_main[0x7f4153e32c30] -> #25 __libc_start_main_alias_2[0x7f4153e32ce0] -> #26 _start[0x55dfa9c4a470] Mar 29 03:03:54 SERVER dovecot-HOST: lmtp(cobb)<4008073><PiAQHoiIyGmJKD0Ay7SJiA>: Fatal: master: service(lmtp): child 4008073 killed with signal 6 (core dumped) Mar 29 03:04:05 SERVER postfix/lmtp[4008072]: 005083DC75D: to=<MYADDRESS@MYDOMAIN>, orig_to=<ANOTHER@ANOTHERDOMAIN>, relay=SERVERNAME[private/dovecot-lmtp], delay=1740676, delays=1740674/0.25/0.04/1.5, dsn=4.4.2, status=deferred (lost connection with SERVERNAME[private/dovecot-lmtp] while sending end of data -- message may be sent more than once) The only message in .dovecot.sieve.log is: fail2ban: line 23: error: failed to read input message: internal error occurred: refer to server log for more information. [2026-04-01 18:54:13]. Thanks in advance for any thoughts! Graham

2 1

Broken table in dovecot-pw manual
by Célestin Matte 01 Apr '26

01 Apr '26

Hello, I just noticed while reading the dovecot-pw man on Arch Linux that the table in the -r option is broken (missing newline between row): | Scheme | Minimum | Maximum | Default | | ------ | ------- | ------- | ------- | | BLF-CRYPT | 4 | 31 | 5 | | SHA256-CRYPT | 1000 | 999999999 | 5000 | | SHA512-CRYPT | 1000 | 999999999 | 5000 | Regards, -- Célestin Matte

2 1

dovecot.list.index.log owned by root: why?
by Stefan G. Weichinger 01 Apr '26

01 Apr '26

I use these sql-queries to let all mailboxes be accessed by the uid=1001: passdb sql { default_password_scheme = MD5-CRYPT passdb_sql_query = SELECT username as user, password, \ '/home/vmail/%{user | domain }/%{user}' as userdb_home, 'maildir:/home/vmail/%{user | domain }/%{user}' as userdb_mail,\ 1001 as userdb_uid, 1001 as userdb_gid FROM mailbox WHERE username = '%{user}' AND active = '1' } userdb prefetch { } ( I assume this following query isn't used then anymore) userdb sql { userdb_sql_query = SELECT username as user, password, \ '/home/vmail/%{user | domain }/%{user}' as userdb_home, 'maildir:/home/vmail/%{user | domain }/%{user}' as userdb_mail,\ 1001 as userdb_uid, 1001 as userdb_gid \ FROM mailbox WHERE username = '%{user}' AND active = '1' userdb_sql_iterate_query = SELECT userid AS username, domain FROM users } id 1001 uid=1001(vmail) gid=1001(vmail) groups=1001(vmail),118(dovecot) I get errors like: Apr 01 11:43:05 imap(logs(a)xunil.at)<1564491><N8oZ6WJO/uwgAQRwHwsMRX9ul+gRMpfY>: Error: open(/home/vmail/xunil.at/logs(a)xunil.at/dovecot.list.index.log) failed: Permission denied (euid=1001(vmail) egid=1001(vmail) missing +r perm: /home/vmail/xunil.at/logs(a)xunil.at/dovecot.list.index.log) ls -l /home/vmail/xunil.at/logs(a)xunil.at/ total 944 drwx------ 2 vmail vmail 622592 Apr 1 11:43 cur -rw------- 1 vmail vmail 0 Jul 30 2021 dovecot-acl-list -rw------- 1 vmail vmail 3304 Apr 1 11:35 dovecot.index -rw------- 1 vmail vmail 202444 Apr 1 11:43 dovecot.index.cache -rw------- 1 vmail vmail 2908 Apr 1 11:43 dovecot.index.log -rw------- 1 vmail vmail 32892 Apr 1 11:35 dovecot.index.log.2 -rw------- 1 vmail vmail 91 Feb 9 2024 dovecot-keywords -rw------- 1 root root 5744 Apr 1 10:30 dovecot.list.index -rw------- 1 root root 480 Apr 1 10:52 dovecot.list.index.log [..] Why do these 2 files get owned by root now ... ? All files below "/home/vmail" should be owned by vmail:vmail I ran chown, and chgrp, sure .. but the errors return. How to fix this? Thanks in advance!

2 5

cannot get IOS or MacOSX to connect to dovecot:995 since upgraded Mac or iPhone
by Bill Scheding 01 Apr '26

01 Apr '26

Versions: [wls(a)www.wls.org]$ uname -a Linux www.wls.org 3.10.0-1160.119.1.el7.x86_64 #1 SMP Tue Jun 4 14:43:51 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux [wls(a)ww.wls.org]$ dovecot --version 2.2.36 (1f10bfa63) My Certs: Testing cert dovecot.key unable to load certificate 139668060415888:error:0906D06C:PEM routines:PEM_read_bio:no start line:pem_lib.c:707:Expecting: TRUSTED CERTIFICATE lrwxrwxrwx 1 root root 21 Mar 25 15:44 dovecot.key -> dovecot.key.old_sep_2 Testing chain dovecot.pem SHA1 Fingerprint=4A:29:34:1D:D5:9C:67:59:FA:31:7E:FF:F4:53:F8:DB:25:73:15:07 subject= /OU=IMAP server/CN=imap.example.com/emailAddress=postmaster@example.com issuer= /OU=IMAP server/CN=imap.example.com/emailAddress=postmaster@example.com serial=C8AA4C688A3F2638 b5bd7939 notBefore=Sep 2 20:17:33 2018 GMT notAfter=Sep 2 20:17:33 2019 GMT lrwxrwxrwx 1 root root 21 Mar 25 15:44 dovecot.pem -> dovecot.crt.old_sep_2 New Certs: Testing key ca.key.3.13.4 RSA key ok lrwxrwxrwx 1 root root 31 Mar 13 14:14 ca.key.3.13.4 -> ../../tls/private/ca.key.3.13.4 Testing chain ca.crt.3.13.4 SHA1 Fingerprint=79:69:88:2A:E0:BF:58:A8:21:E3:88:12:8D:45:20:4F:FD:68:33:63 subject= /C=XX/ST= /L= /O= /OU=IMAP server/CN=imap.example.com/emailAddress=postmaster@example.com issuer= /C=XX/ST= /L= /O= /OU=IMAP server/CN=imap.example.com/emailAddress=postmaster@example.com serial=B912DD19FEDC441C 402b4e2a notBefore=Mar 13 20:02:58 2026 GMT notAfter=Mar 13 20:02:58 2027 GMT lrwxrwxrwx 1 root root 29 Mar 13 14:13 ca.crt.3.13.4 -> ../../tls/certs/ca.crt.3.13.4 They install OK, dovecot starts; but iPhone and mac cannot connect to pop3 Cannot get my iPhone or Mac to accept new certs from lets encrypt, et. al. This is a new problem, started recently. My existing cert expired in 2016 William

2 1

Variable expansion syntax: Filter "default" throws error (unwanted)
by Johannes Nohl 01 Apr '26

01 Apr '26

I am using dovecot 2.4.2 (almost) with new config language and I have a working configuration. However, the check for disabled users throws permanently errors in the log file, whenever a user is missing the ldap attribute for disabled. This is - in my view - due to a misfunction of Filter "default". passdb ldap { driver = ldap ldap_bind = yes ldap_filter = (&(|(objectClass=posixAccount)(objectClass=mailAccount))(uid=%{user})) fields { user = %{ldap:uid} nologin = %{ldap:shadowInactive | default(null)} reason = The account for this email address is disabled. } } This results in the following log line: 2026-03-31T00:46:31.102690+02:00 mailserver dovecot: auth(test,ipv4,sasl:plain)<YE81n0VOVuofEeSD>: Error: ldap: auth_passdb_post settings: Failed to parse configuration: Failed to expand passdb_fields/nologin setting variables: ldap: No such attribute 'shadowinactive' The right behaviour would be no logging on login success. Because the Filter "default" is intended to suppress any errors ("When value is missing or empty, you can use the default filter to provide value. Missing variables will cause errors and must be negated with default. This does not apply to all providers, some providers return empty when value is missing."). https://doc.dovecot.org/2.4.2/core/settings/variables.html#variable-expansi… As you may have seen I had to borrow null-value from sql db config also to make nologin ignoring a non present attribute. This is undocumented obviously. Instead, a non-working tip is provided ("Changed: 2.4.0 Extra fields can now also be set to empty string, "). However, the following does not work: "nologin = {ldap:shadowinactive | default("")}". https://doc.dovecot.org/2.4.2/core/settings/variables.html Also, the documentation is missing/hiding the part which explains that "default()" can be used to avoid error logs. PR regarding the documentation source is sent already. See "Fails if the attribute is not present, unless the ` <missing part>" https://doc.dovecot.org/2.4.0/core/config/auth/databases/ldap.html#ldap-spe… Is there another way to verify if account is disabled? -- Johannes Nohl postmaster i-t-cloud -- Johannes Nohl postmaster(a)i-t-cloud.de I am using dovecot 2.4.2 (almost) with new config language and I have a working configuration. However, the check for disabled users throws permanently errors in the log file, whenever a user is missing the ldap attribute for disabled. This is - in my view - due to a misfunction of Filter "default". passdb ldap { driver = ldap ldap_bind = yes ldap_filter = (&(|(objectClass=posixAccount)(objectClass=mailAccount))(uid=%{user})) fields { user = %{ldap:uid} nologin = %{ldap:shadowInactive | default(null)} reason = The account for this email address is disabled. } } This results in the following log line: *2026-03-31T00:46:31.102690+02:00 mailserver dovecot: auth(test,ipv4,sasl:plain)<YE81n0VOVuofEeSD>: Error: ldap: auth_passdb_post settings: Failed to parse configuration: Failed to expand passdb_fields/nologin setting variables: ldap: No such attribute 'shadowinactive' The right behaviour would be no logging on login success. Because the Filter "default" is intended to suppress any errors ("When value is missing or empty, you can use the default filter to provide value. Missing variables will cause errors and must be negated with default. This does not apply to all providers, some providers return empty when value is missing."). https://doc.dovecot.org/2.4.2/core/settings/variables.html#variable-expansi… As you may have seen I had to borrow null-value from sql db config also to make nologin ignoring a non present attribute. This is undocumented obviously. Instead, a non-working tip is provided ("Changed: 2.4.0 Extra fields can now also be set to empty string, "). However, the following does not work: "nologin = {ldap:shadowinactive | default("")}". https://doc.dovecot.org/2.4.2/core/settings/variables.html Also, the documentation is missing/hiding the part which explains that "default()" can be used to avoid error logs. PR regarding the documentation source is sent already. See "Fails if the attribute is not present, unless the ` <missing part>" https://doc.dovecot.org/2.4.0/core/config/auth/databases/ldap.html#ldap-spe… Is there another way to verify if account is disabled? -- Johannes Nohl postmaster i-t-cloud -- Johannes Nohl postmaster(a)i-t-cloud.de

2 1

[BUG] 2.4.3 SIGSEGV in fts_solr
by Nick O'Connor 01 Apr '26

01 Apr '26

Dovecot 2.4.3 crashes with SIGSEGV in indexer-worker and lmtp during FTS Solr indexing. The crash is a use-after-free triggered when the HTTP client does a DNS lookup for the Solr host. Environment: - Dovecot 2.4.3 (Alpine 3.23 / musl) - Linux x86_64 - Filesystem: maildir on ZFS - Solr 10.0.0 - fts_solr plugin with DNS-based Solr URL dovecot -n: # 2.4.3 (e278b1e09b): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.3 (0bf9ee48) # OS: Linux 6.12.74+deb13+1-amd64 x86_64 dovecot_config_version = 2.4.0 auth_mechanisms = oauthbearer xoauth2 dovecot_storage_version = 2.4.0 fts_autoindex = yes fts_search_add_missing = yes mail_always_cache_fields = date.save mail_driver = maildir mail_plugins { fts = yes fts_solr = yes } protocols = imap lmtp sieve ssl = required fts solr { url = http://solr.example.com/solr/dovecot } (LDAP userdb/passdb, pigeonhole sieve, imapsieve for spam learning, and oauth2 passdb omitted) How to reproduce: The crash occurs in the indexer-worker when processing multiple user mailboxes sequentially for FTS indexing, using a DNS hostname for the Solr URL. Steps: 1. Configure fts_solr with a DNS-based URL (not an IP address) 2. Have the indexer-worker process mailboxes for more than one user (e.g. fts_autoindex = yes with multiple users, or manual doveadm index -A) 3. The first user session completes successfully. On the second user session, the indexer-worker crashes with SIGSEGV during the DNS lookup for the Solr host. Reproduces reliably on musl (Alpine) due to aggressive memory reuse. Likely also affects glibc but may not crash immediately due to delayed reuse of freed memory. Root cause: The solr_http_client singleton outlives the user session that created it. Its event chain holds a ref on the mail_storage_service_user event, keeping it alive after the user is freed. The SETTINGS_EVENT_INSTANCE on that event still points to the already-freed settings_instance. On the next user session, dns_lookup() walks the stale event chain and dereferences the dangling pointer in settings_instance_get(). Stack trace (from core dump, debug build with musl-dbg): #0 strlen(s=0x415641d189485741) -- SIGSEGV, freed/reused memory #1 p_strdup() strfuncs.c:56 #2 event_add_str(key="protocol", value=...) lib-event.c:1099 #3 settings_instance_get() settings.c:2521 #4 settings_get_real() settings.c:2706 #5 settings_get_full() settings.c:2915 #6 settings_get(dns_client_setting_parser_info) settings.c:2976 #7 dns_client_init() dns-lookup.c:465 #8 dns_client_init_handle_failure() dns-lookup.c:317 #9 dns_lookup("solr.example.com") dns-lookup.c:337 #10 http_client_host_shared_lookup() http-client-host.c:166 #11 http_client_host_shared_refresh() http-client-host.c:195 #12-#19 http_client queue/host/request submit chain #20 http_client_request_continue_payload() http-client-request.c:1170 #21 http_client_request_send_payload() http-client-request.c:1261 #22 solr_connection_post_more() solr-connection.c:269 Proposed fix: Destroy solr_http_client in solr_connection_deinit() so it is recreated with a fresh event chain on the next user session: --- a/src/plugins/fts-solr/solr-connection.c +++ b/src/plugins/fts-solr/solr-connection.c @@ -117,6 +117,8 @@ void solr_connection_deinit(struct solr_connection **_conn) *_conn = NULL; event_unref(&conn->event); + if (solr_http_client != NULL) + http_client_deinit(&solr_http_client); i_free(conn->http_host); i_free(conn->http_base_url); I've been running for few days with the patch applied. FTS indexing across multiple user sessions completes without crashes using a DNS-based Solr URL. Please let me know if there's anything else that would be helpful. The core files have sensitive information so I've omitted them from the report. -Nick Dovecot 2.4.3 crashes with SIGSEGV in indexer-worker and lmtp during FTS Solr indexing. The crash is a use-after-free triggered when the HTTP client does a DNS lookup for the Solr host. Environment: - Dovecot 2.4.3 (Alpine 3.23 / musl) - Linux x86_64 - Filesystem: maildir on ZFS - Solr 10.0.0 - fts_solr plugin with DNS-based Solr URL dovecot -n: # 2.4.3 (e278b1e09b): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.3 (0bf9ee48) # OS: Linux 6.12.74+deb13+1-amd64 x86_64 dovecot_config_version = 2.4.0 auth_mechanisms = oauthbearer xoauth2 dovecot_storage_version = 2.4.0 fts_autoindex = yes fts_search_add_missing = yes mail_always_cache_fields = date.save mail_driver = maildir mail_plugins { fts = yes fts_solr = yes } protocols = imap lmtp sieve ssl = required fts solr { url = http://solr.example.com/solr/dovecot } (LDAP userdb/passdb, pigeonhole sieve, imapsieve for spam learning, and oauth2 passdb omitted) How to reproduce: The crash occurs in the indexer-worker when processing multiple user mailboxes sequentially for FTS indexing, using a DNS hostname for the Solr URL. Steps: 1. Configure fts_solr with a DNS-based URL (not an IP address) 2. Have the indexer-worker process mailboxes for more than one user (e.g. fts_autoindex = yes with multiple users, or manual doveadm index -A) 3. The first user session completes successfully. On the second user session, the indexer-worker crashes with SIGSEGV during the DNS lookup for the Solr host. Reproduces reliably on musl (Alpine) due to aggressive memory reuse. Likely also affects glibc but may not crash immediately due to delayed reuse of freed memory. Root cause: The solr_http_client singleton outlives the user session that created it. Its event chain holds a ref on the mail_storage_service_user event, keeping it alive after the user is freed. The SETTINGS_EVENT_INSTANCE on that event still points to the already-freed settings_instance. On the next user session, dns_lookup() walks the stale event chain and dereferences the dangling pointer in settings_instance_get(). Stack trace (from core dump, debug build with musl-dbg): #0 strlen(s=0x415641d189485741) -- SIGSEGV, freed/reused memory #1 p_strdup() strfuncs.c:56 #2 event_add_str(key="protocol", value=...) lib-event.c:1099 #3 settings_instance_get() settings.c:2521 #4 settings_get_real() settings.c:2706 #5 settings_get_full() settings.c:2915 #6 settings_get(dns_client_setting_parser_info) settings.c:2976 #7 dns_client_init() dns-lookup.c:465 #8 dns_clien t_init_handle_failure() dns-lookup.c:317 #9 dns_lookup("solr.example.com") dns-lookup.c:337 #10 http_client_host_shared_lookup() http-client-host.c:166 #11 http_client_host_shared_refresh() http-client-host.c:195 #12-#19 http_client queue/host/request submit chain #20 http_client_request_continue_payload() http-client-request.c:1170 #21 http_client_request_send_payload() http-client-request.c:1261 #22 solr_connection_post_more() solr-connection.c:269 Proposed fix: Destroy solr_http_client in solr_connection_deinit() so it is recreated with a fresh event chain on the next user session: --- a/src/plugins/fts-solr/solr-connection.c +++ b/src/plugins/fts-solr/solr-connection.c @@ -117,6 +117,8 @@ void solr_connection_deinit(struct solr_connection **_conn) *_conn = NULL; event_unref(&conn->event); + if (solr_http_client != NULL) + http_client_deinit(&solr_http_client); i_free(conn->http_host); i_free(conn->http_base_url); I've been running for few days with the patch applied. FTS indexing across multiple user sessions completes without crashes using a DNS-based Solr URL. Please let me know if there's anything else that would be helpful. The core files have sensitive information so I've omitted them from the report. -Nick

1 0

migration from 2.3 to 2.4 : postfix can't deliver via lmtp
by Stefan G. Weichinger 31 Mar '26

31 Mar '26

I am in the process of upgrading and rewriting my config. I can access IMAP etc ... so my database access is working. I have issues with LMTP: postfix can't deliver to dovecot. The postfix-confiog wasn't touched at all. the error: Mar 27 11:46:37 co dovecot: auth(stefan(a)oops.co.at): Error: userdb: client doesn't have lookup permissions for this user: userdb reply doesn't contain uid (to bypass this check, set: service auth { unix_listener /run/dovecot/auth-userdb { mode=0777 } }) What I don't understand: I configure this: service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } } service auth-worker { user = postfix } service lmtp { user = vmail unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0660 user = postfix } } protocol lmtp { mail_plugins = sieve postmaster_address = logs(a)xunil.at } And in postfix: virtual_transport = lmtp:unix:private/dovecot-lmtp virtual_uid_maps = static:5000 virtual_gid_maps = static:5000 local_transport = virtual local_recipient_maps = $virtual_mailbox_maps smtpd_sasl_auth_enable = yes smtpd_sasl_type = dovecot smtpd_sasl_path = private/auth Where does "/run/dovecot/auth-userdb" come from? I understand that according to my config /var/spool/postfix/private/auth should be used? ls /var/spool/postfix/private/auth -l srw-rw-rw- 1 postfix postfix 0 Mar 27 11:45 /var/spool/postfix/private/auth ls /var/spool/postfix/private/dovecot-lmtp -l srw-rw---- 1 postfix postfix 0 Mar 27 11:45 /var/spool/postfix/private/dovecot-lmtp I'd appreciate any quick help here ... while googling and testing around ... thanks!

2 17

upgrade to 2.4
by John Hill 31 Mar '26

31 Mar '26

Dovecot may go down as one of the best/worst software in its category. I'm staying on Debian 12 doing backports, till the dust settles several times. --john

1 0

Fwd: dovecot mailing list probe message
by Jaco Kroon 30 Mar '26

30 Mar '26

Hi, It seems like the list system is breaking DKIM - triggering bounces, resulting in unsuscribes. Is there recommendations on how to deal with this? Looks like it relates 100% to the addition of the footer: ______________________________________________ dovecot mailing list -- dovecot(a)dovecot.org To unsubscribe send an email to dovecot-leave(a)dovecot.org Kind regards, Jaco -------- Forwarded Message -------- Subject: dovecot mailing list probe message Date: Mon, 30 Mar 2026 06:32:58 +0000 From: dovecot-bounces+a190cb9ae5d94d8fa6e2af68fc964a7aaa13256b(a)dovecot.org To: jaco(a)uls.co.za This is a probe message. You can ignore this message. The dovecot(a)dovecot.org mailing list has received a number of bounces from you, indicating that there may be a problem delivering messages to jaco(a)uls.co.za. A sample is attached below. Please examine this message to make sure there are no problems with your email address. You may want to check with your mail administrator for more help. You don't need to do anything to remain an enabled member of the mailing list. If you have any questions or problems, you can contact the mailing list owner at dovecot-owner(a)dovecot.org Hi, It seems like the list system is breaking DKIM - triggering bounces, resulting in unsuscribes. Is there recommendations on how to deal with this? Looks like it relates 100% to the addition of the footer: ______________________________________________ dovecot mailing list -- [1]dovecot(a)dovecot.org To unsubscribe send an email to [2]dovecot-leave(a)dovecot.org Kind regards, Jaco -------- Forwarded Message -------- Subject: dovecot mailing list probe message Date: Mon, 30 Mar 2026 06:32:58 +0000 From: [3]dovecot-bounces+a190cb9ae5d94d8fa6e2af68fc964a7aaa13256b(a)dovecot.org To: [4]jaco(a)uls.co.za This is a probe message. You can ignore this message. The [5]dovecot(a)dovecot.org mailing list has received a number of bounces from you, indicating that there may be a problem delivering messages to [6]jaco(a)uls.co.za. A sample is attached below. Please examine this message to make sure there are no problems with your email address. You may want to check with your mail administrator for more help. You don't need to do anything to remain an enabled member of the mailing list. If you have any questions or problems, you can contact the mailing list owner at [7]dovecot-owner(a)dovecot.org References Visible links 1. mailto:dovecot@dovecot.org 2. mailto:dovecot-leave@dovecot.org 3. mailto:dovecot-bounces+a190cb9ae5d94d8fa6e2af68fc964a7aaa13256b@dovecot.org 4. mailto:jaco@uls.co.za 5. mailto:dovecot@dovecot.org 6. mailto:jaco@uls.co.za 7. mailto:dovecot-owner@dovecot.org

3 4

Update to v2.4.3 breaks ldap connection
by markus-dovecot＠doits.de 30 Mar '26

30 Mar '26

Unfortunately the upgrade to v2.4.3 broke the ldap connection. I have configured an ldap connection like this: ``` ldap_uris = ldaps://xxx.com ldap_auth_dn = uid=xxx,ou=general accounts,dc=xxx,dc=com ldap_auth_dn_password = xxx ldap_base = dc=xxx,dc=com passdb ldap { ldap_bind = yes [...] } ``` v2.4.3 cannot connect and says: ``` auth: Error: ldap(ldaps://xxx.com636): Can't connect to server: ldaps://xxx.com ``` Ldap server logs: ``` ACCEPT from IP=[XXX]:45674 (IP=[::]:636) TLS established tls_ssf=256 ssf=256 tls_proto=TLS1.3 tls_cipher=AES-256-GCM closed (connection lost) ``` Downgrade to dovecot v2.4.2 makes it work again. Was there any ldap change in v2.4.3 that required a config change? Using ubuntu 24.04 with the dovecot ppa, now forced version 2.4.2 by using https://repo.dovecot.org/ce-2.4.2/ubuntu/noble

4 6

Dovecot 2.4.3 virtual now broken even more
by sev monster 30 Mar '26

30 Mar '26

As of 2.4.2, Dovecot no longer crashed and broken config vars no longer caused it to error out, so I finally (reluctantly) switched to it over 2.3, though I had to disable/change a few things to get it to work. However, my virtual namespaces were still broken, since the `autosubscribe = yes` option would cause the driver to attempt to create the virtual directories, and fail when they already existed. Turning off autosubscribe meant that the folders were not visible to my users without manually subscribing. With 2.4.3, now the virtual configs that "worked" before now cause Dovecot to error out completely! Yay It seems this commit introduced a "feature" that restricts the virtual driver to the fs list format: https://github.com/dovecot/core/commit/b4a4a32361b8f0e68ef230add6467eddd0ff… But why? Is fs the only format that works? But maildir++ worked in both 2.3 and in previous versions of 2.4. The 2.4.3 docs (still) also recommend switching to maildir++ if desired: https://doc.dovecot.org/2.4.3/core/plugins/virtual.html#virtual-mailbox-plu… In my config, I use maildir for everything. That means in my mailboxes and all my namespaces. But with this change, I must now use fs as my list format for the virtuals. But, I can't do that, because all `list = yes` namespaces in use by a mailbox must use the same list format... So now my previously invisible virtual folders now cause Dovecot to fall over and I have to completely remove the virtual declarations from my config. What am I supposed to do now?

3 2

Executing a sieve-extprograms pipe script as non-root
by Roland Hieber 29 Mar '26

29 Mar '26

Hi, Ultimately I'm trying to call procmail via a `pipe "procmail";` in my Sieve script on Dovecot 2.4.1. I have therefore created the respective wrapper script in /usr/lib/dovecot/sieve-pipe/procmail, but I noted that the script is apparently run as root. With some debug output in the wrapper script, I see: # `id` output uid=0(root) gid=1059(rhi) groups=1059(rhi),116(dovecot) # `pstree -s -u $$` systemd(1)---dovecot(1064)---lmtp(266577,rhi)---procmail(266706,root)---pstree(266711) This Dovecot gets mail delivered via LMTP from another server. 1059 (rhi) is my local user ID on the IMAP server both in /etc/passwd and in /etc/dovecot/users (using auth-passwdfile.conf.ext in 10-auth.conf instead of auth-system.conf.ext), since mail needs to be delivered and chown'ed correctly into Maildirs that should be user-accessible. However I don't understand how the `procmail` wrapper can be run as the root user rights when the LMTP process starting it is running as my own user?!? I'd like to prevent procmail from running as root as far as possible, so for now I've been able to work around this by wrapping the procmail call into an additional `sudo -U $USER` (after determining the user who owns the target maildir), but I'd like to understand the problem a bit further and like to know if this is really how calling sieve-extprograms is supposed to work – I'd have expected that the external scripts are also run as my unprivileged user. I'm running a fairly standard config on Debian stable (dovecot package version 1:2.4.1+dfsg1-6+deb13u2) with only minimal changes by enabling the passwdfile backend and some sieve plugins. Thanks for any insights, - Roland -- Roland Hieber, Pengutronix e.K. | rhi(a)pengutronix.de | Steuerwalder Str. 21 | https://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |

6 8

dovecot 2.4.x director
by Maciej Milaszewski 27 Mar '26

27 Mar '26

HI Has anyone managed to create a fork or other solution that provides director functionality? A small setup where it can be managed, for example, with Rabit/Redis, is one thing, but not a larger environment. The documentation for 2.4.x seems to have something like this: https://doc.dovecot.org/2.4.3/howto/lua_director.html "This is an unsupported method of running Dovecot. Caveat emptor. It is only intended for small-scale deployments – this is NOT designed to scale for more than a few servers."

2 1

Dovecot Security Advisory OXDC-2026-0001
by Aki Tuomi 27 Mar '26

27 Mar '26

Hi! We're sharing our latest advisory with you and like to thank everyone who contributed in finding and solving those vulnerabilities. This advisory is also published at https://documentation.open-xchange.com/dovecot/security/advisories/html/202… --- Internal reference: DOV-7830 Type: CWE-1250 (Improper Preservation of Consistency Between Independent Representations of Shared State) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot CE core 2.4.0 First fixed revision: OX Dovecot CE core 2.4.1 Discovery date: 2025-07-24 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: Erik <erik(a)broadlux.com> CVE: CVE-2025-30189 CVSS: 7.4 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N) Details: v2.4 regression: auth cache broken with several passdb / userdb. When cache is enabled, some passdb/userdb drivers incorrectly cache all users with same cache key, causing wrong cached information to be used for these users. Risk: After cached login, all subsequent logins are for same user. No publicly available exploits are known. Solution: Install fixed version or disable caching either globally or for the impacted passdb/userdb drivers. --- Internal reference: DOV-8349 Type: CWE-20 (Improper Input Validation) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot CE core 2.4.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2025-11-04 Solution date: 2026-03-27 Disclosure date: 2026-03-27 CVE: CVE-2025-59028 CVSS: 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L) Details: Invalid base64 authentication can cause DoS for other logins. When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Risk: Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. No publicly available exploits are known. Solution: Install fixed version or disable concurrency in login processes (heavy perfomance penalty on large deployments). --- Internal reference: DOV-8508 Type: CWE-20 (Improper Input Validation) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot CE core 2.4.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2025-11-29 Solution date: 2026-03-27 Disclosure date: 2026-03-27 CVE: CVE-2025-59032 CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) Details: v2.4/v3.1 regression: Pigeonhole: ManageSieve panic occurs with sieve-connect as a client. ManageSieve AUTHENTICATE command crashes when using literal as SASL initial response. Risk: This can be used to crash ManageSieve service repeatedly, making it unavailable for other users. No publicly available exploits are known. Solution: Control access to ManageSieve port, or disable the service if it's not needed. Alternatively upgrade to a fixed version. --- Internal reference: DOV-8584 Type: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot Pro core 2.3.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2025-12-29 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: cavid@yeswehack CVE: CVE-2025-59031 CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N) Details: decode2text.sh OOXML extraction may follow symlinks and read unintended files during indexing. Dovecot has provided a script to use for attachment to text conversion. This script unsafely handles zip-style attachments. Risk: Attacker can use specially crafted OOXML documents to cause unintended files on the system to be indexed and subsequently ending up in FTS indexes. No publicly available exploits are known. Solution: Do not use the provided script, instead, use something else like FTS tika. --- Internal reference: DOV-8591 Type: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot Pro core 2.3.0 First fixed revision: OX Dovecot CE core 2.4.0 Discovery date: 2026-01-07 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: strokep@yeswehack CVE: CVE-2026-0394 CVSS: 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N) Details: auth: Path traversal in passwd-file passdb using `%d` (domain) escapes base directory and opens `/etc/passwd`Pre-auth path traversal in passwd-file passdb using `%d` (domain) escapes base directory and opens `/etc/passwd`. When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or slash has been added to allowed characters, path traversal can happen if the domain component is directory partial. Risk: This allows inadvertently reading /etc/passwd (or some other path which ends with passwd). If this file contains passwords, it can be used to authenticate wrongly, or if this is userdb, it can unexpectly make system users appear valid users. No publicly available exploits are known. Solution: Upgrade to fixed version, or use different authentication scheme that does not rely on paths. Alternatively you can also ensure that the per-domain passwd files are in some other location, such as /etc/dovecot/auth/%d. --- Internal reference: DOV-8775 Type: CWE-90 (Improper Neutralization of Special Elements used in an LDAP Query ('LDAP Injection')) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot CE core 2.4.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2026-02-20 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: cookiejack15@yeswehack CVE: CVE-2026-27860 CVSS: 3.7 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N) Details: v2.4/v3.1 regression: auth-ldap is not escaping usernames. If auth_username_chars is empty, it is possible to inject arbitrary LDAP filter to Dovecot's LDAP authentication. Risk: This leads to potentially bypassing restrictions and allows probing of LDAP structure. No publicly available exploits are known. Solution: Do not clear out auth_username_chars, or install fixed version. --- Internal reference: DOV-8781 Type: CWE-89 (Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot CE core 2.4.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2026-02-23 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: whisperer@yeswehack CVE: CVE-2026-24031 CVSS: 7.7 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L) Details: v2.4/v3.1 regression: SQL injection allows bypassing authentication. Dovecot SQL based authentication can be bypassed when auth_username_chars is cleared by admin. Risk: This vulnerability allows bypassing authentication for any user and user enumeration. No publicly available exploits are known. Solution: Do not clear auth_username_chars. If this is not possible, install latest fixed version. --- Internal reference: DOV-8787 Type: CWE-400 (Uncontrolled Resource Consumption) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot CE core 2.4.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2026-02-24 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: djvirus@yeswehack CVE: CVE-2026-27859 CVSS: 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L) Details: v3.0.2+ regression: Message headers MIME parameter parsing can cause excessive CPU usage. A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. Risk: A suitably formatted mail message causes mail delivery process to consume large amounts of CPU time. No publicly available exploits are known. Solution: Use MTA capabilities to limit RFC 2231 MIME parameters in mail messages, or upgrade to fixed version where the processing is limited. --- Internal reference: DOV-8816 Type: CWE-400 (Uncontrolled Resource Consumption) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot Pro core 2.3.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2026-02-27 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: whisperer@yeswehack CVE: CVE-2026-27857 CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L) Details: imap-login: Excessive memory usage DoS. Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage. Longer commands will result in client disconnection. This 1 MB can be left allocated for longer time periods by not sending the command ending LF. So attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Risk: Attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. No publicly available exploits are known. Solution: Install fixed version, there is no other remediation. --- Internal reference: DOV-8818 Type: CWE-400 (Uncontrolled Resource Consumption) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot Pro core 2.3.0, OX Dovecot CE core 2.4.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2026-02-28 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: ilyar@yeswehack CVE: CVE-2026-27858 CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) Details: managesieve-login out-of-memory DoS. Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Risk: Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. No publicly available exploits are known. Solution: Protect access to managesieve protocol, or install fixed version. --- Internal reference: DOV-8830 Type: CWE-287 (Improper Authentication) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot Pro core 2.3.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2026-03-04 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: bksparajuli@yeswehack CVE: CVE-2026-27856 CVSS: 7.4 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N) Details: doveadm: Credentials verified without timing safety. Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Risk: Figuring out the credential will lead into full access to the affected component. No publicly available exploits are known. Solution: Limit access to the doveadm http service port, install fixed version. --- Internal reference: DOV-8859 Type: CWE-294 (Authentication Bypass by Capture-replay) Component: core Report confidence: Confirmed Solution status: Fixed by vendor Last affected revision: OX Dovecot Pro core 2.3.0 First fixed revision: OX Dovecot CE core 2.4.3 Discovery date: 2026-03-09 Solution date: 2026-03-27 Disclosure date: 2026-03-27 Researcher credits: hamizanazman@yeswehack CVE: CVE-2026-27855 CVSS: 6.8 (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N) Details: auth: OTP driver vulnerable to replay attack. Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. Risk: An attacker able to observe an OTP exchange is able to log in as the user. No publicly available exploits are known. Solution: If authentication happens over unsecure connection, switch to SCRAM protocol. Alternatively ensure the communcations are secured, and if possible switch to OAUTH2 or SCRAM.

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Imap Sieve errors in 2.4.2
by Alberto 26 Mar '26

26 Mar '26

Hi, I have a Dovecot docker image with last version (2.4.2). I'm getting some errors, last time a few minutes ago, when dragging some emails into a folder I had just created. ... Mar 26 10:48:20 imap(alberto(a)bersol.info)<451><wHkgJepNsLRYDtBg>: Info: Mailbox INBOX.carpetanueva: Mailbox created Mar 26 10:48:24 imap(alberto(a)bersol.info)<397><x8N6YuhNMs9YDtBg>: Panic: file imap-sieve-storage.c: line 216 (imap_sieve_add_mailbox_event): assertion failed : (ismt->src_box == NULL || ismt->src_box == src_box) Mar 26 10:48:24 imap(alberto(a)bersol.info)<397><x8N6YuhNMs9YDtBg>: Error: Raw backtrace: #1 [unw_get_proc_name() failed: -10] -> #2 [unw_get_proc_name() failed: -10] -> #3 i_panic[0x7fbaed2ee8ab] -> #4 [unw_get_proc_name() failed: -1] Mar 26 10:48:24 imap(alberto(a)bersol.info)<397><x8N6YuhNMs9YDtBg>: Fatal: master: service(imap): child 397 killed with signal 6 (core dumped) This breaks Dovecot and I have to restart the container, but it doesn't fix it either. When I access again, I've receive this errors again, until I disable sieve in the imap.conf: conf.d/20-imap.conf ------------------- ... protocol imap { # Space separated list of plugins to load (default is global mail_plugins). mail_plugins { # imap_sieve = yes imap_quota = yes last_login = yes } And I have to keep "imap_sieve" disabled. Regards, Alberto

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Issues with doveadm sync
by cryintothebluesky＠gmail.com 21 Mar '26

21 Mar '26

Hello, I have two replica IMAP servers both running dovecot-2.4.2: imap1.example.com imap2.example.com I'm observing the following issues when replicating mailboxes with doveadm sync: 1. Permission errors with public and shared mailboxes For this test I delete all mailboxes on imap2.example.com and then use full sync from imap1.example.com to replicate mailboxes: # doveadm sync -f -s "" -N -l 10 -u ${user:?} ${server:?} The first time I run this command, the following error messages are logged: doveadm(XXX(a)example.com)<1363><eZzOJic5vWlTBQAAMBZ7fQ>: Error: brain S: Can't create mailbox Shared/support(a)example.com: Permission denied doveadm(XXX(a)example.com)<1334><ZV88Byg5vWk2BQAAMBZ7fQ>: Error: brain S: Can't create mailbox Public/Test: Permission denied If I wait 10 seconds and run the same sync command again, all mailboxes are replicated correctly. This only happens with public and shared mailboxes. I'm not sure of the exact cause, but it looks as if there is a race condition, where on the target server replicated ACLs are not applied immediately and this results in permission errors. Can anyone confirm the root cause? 2. Mailboxes are not always synchronised correctly For this test I'm using stateful sync. The man page states it performs a two-way sync, hence both server should end up with the same state. 1) I log into imap2.example.com and move some messages from Inbox to Drafts and Junk folders. 2) On imap1.example.com I run: doveadm sync -s "${state}" -N -l 10 -u ${user:?} ${server:?} 3) I log into imap1.example.com and sometimes observe the recently moved messages missing from Drafts and/or Junk folders. 4) The only way to resolve this issue is to either run full sync from imap1.example.com or to run another stateful sync but from imap2.example.com. Can anyone confirm if this is a bug or if stateful sync is required to be run on both IMAP servers against each other?

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Error: ldap: auth_passdb_post settings
by Ruud Baart 21 Mar '26

21 Mar '26

Dovecot 2.4.1 works fine on my Debian Trixie server. I use LDAP as backend for the users. I don't have problems. Authentication works fine. However logging show every time the following line: auth-worker(<user name@domain,::1)<109040><3v5ddOlJvrgAAAAAAAAAAAAAAAAAAAAB>: request [7]: Error: ldap: auth_passdb_post settings: Failed to parse configuration: Failed to expand passdb_fields/password setting variables: ldap: No such attribute 'userpassword' The LDAP authentication works correct. So I don't understand this message. My correct working LDAP configuration in auth-ldap.conf.ext: passdb ldap { passdb_use_worker = yes passdb_ldap_filter = (&(objectClass=PromptMailUser)(accountStatus=TRUE)(mailDeliveryaddress=%{user})) ldap_bind = yes fields { user = %{ldap:mailDeliveryaddress} password = %{ldap:userPassword} } } userdb ldap { userdb_use_worker = yes userdb_ldap_filter = (&(objectClass=PromptMailUser)(accountStatus=TRUE)(mailDeliveryaddress=%{user})) fields { home = %{ldap:mailBase} mail = %{ldap:mailMessageStore} mail_path = %{ldap:mailMessageStore} quota_storage_size = %{ldap:dovecotQuota} } }

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shared mailbox error
by Marc 19 Mar '26

19 Mar '26

I am getting this error. This file does not exist. Error: t_readlink(/xxxxxx/dbox-alt-root) failed: readlink() failed: Permission denied

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dovecot-2.4.2: doveconf seg fault
by Eray Aslan 16 Mar '26

16 Mar '26

Running dovecot -c /dev/null -n results in: # 2.4.2 (0962ed2104): /dev/null # Pigeonhole version 2.4.2 (767418c3) Program received signal SIGSEGV, Segmentation fault. 0x00007ffff7c0f3a6 in str_to_uint () at ../lib/strnum.c:76 for a user. And the issue seems to be const unsigned char ** vs const char * mismatch: int str_to_uintmax(const char *str, uintmax_t *num_r) { const char *endp = NULL; uintmax_t n; int ret = str_parse_uintmax(str, &n, &endp); if ((ret != 0) || (*endp != '\0')) /* <--- reading via 'const char *' return -1; *num_r = n; return 0; } vs int str_parse_data_uintmax(const unsigned char *data, size_t size, uintmax_t *num_r, const unsigned char **endp_r) { const unsigned char *p = data, *pend = data + size; uintmax_t n = 0; if (p >= pend || *p < '0' || *p > '9') return -1; do { if (n >= ((uintmax_t)-1 / 10)) { if (n > (uintmax_t)-1 / 10) return -1; if ((uintmax_t)(*p - '0') > ((uintmax_t)-1 % 10)) return -1; } n = n * 10 + (*p - '0'); p++; } while (p < pend && *p >= '0' && *p <= '9'); if (endp_r != NULL) *endp_r = p; /* <--- writing via 'const unsigned char *' *num_r = n; return 0; } We don't know enough to choose which one would be preferable so that the interfaces match. It needs an informed decision as it shows up in a bunch of other places as well. More details at: https://bugs.gentoo.org/971191 Thank you -- Eray

1 0

Issues with 2.4.1 & remote postgresql server
by Terry Braun 15 Mar '26

15 Mar '26

Hello, I'm stumped with using a remote postgresql database for authentication. I went through the process once, failed, debugged, failed again. I could successfully use psql to access the remote database from my host machine, so I do not believe the remote access is an issue. I implemented an instance using sqlite3 database and it worked just fine. ``` from auth-sql.conf.ext ``` sql_driver = pgsql pgsql 72.44.55.66 { parameters { sslmode = require user = user password = 123 dbname = db } } I'm using lmtp over sockets to deliver mail to dovecot, in order to isolate any interaction issues. With a postgresql db I get "Mailbox isn't a valid mbox file", but with changes only to auth-sql.conf.ext it fails. I can run the queries from psql and they work. I'm pretty much out of ideas of things to try. - I could not find anything to validate the syntax of the psql data. All the examples had "psql localhots {" - Because of the above, I am wondering if there may be an issue in the postgres driver somehow? - I did look at the documentation for https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-PARAMKEYWO… but I'm unsure what is needed. Thanks for any ideas, help, hints. If someone has an example that works with 2.4.1-4 (7d8c0e5759) on debian 13 that would be great Terry

2 1

How to declare port 143
by Steve Litt 10 Mar '26

10 Mar '26

Hi all, I have Dovecot 2.4.2 working (plain text only) on my Qemu virtual machine, with Claws-Mail able to work with all its files. However, I want to declare the Dovecot server as running on Port 143, and when I do, I dovecot -F throws the error message shown later in this message. If I comment out the explicit port declaration, it works fine, and I want to know why. To the best of my knowledge, my declaration of port 143 exactly matches your 2.4.2 documentation: The following is my attempt to tell Dovecot to serve *explicitly* at port 143: =============================================== # My Dovecot server will operate on Localhost listen = 127.0.0.1 service imap { inet_listener imap-login { port = 143 } # inet_listener imaps { # port = 993 # ssl = yes # } } =============================================== The following is the result: =============================================== [root@dovecotvoid ~]# dovecot -F doveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf: duplicate listener: 143:127.0.0.1 [root@dovecotvoid ~]# =============================================== If I comment out the port = 143, it works. Why is it griping about a duplicate listener? At the bottom of this email is the entire dovecot.conf and the result of dovecot -n, and there are no sub-configuration files in conf.d : =============================================== # Start new configs with the latest Dovecot version numbers here: dovecot_config_version = 2.4.2 # Must be current version dovecot_storage_version = 2.4.2 # Must be current version or earlier # 2.3 is minimum # I only want imap protocols { imap = yes lmtp = no pop3 = no } # My Dovecot server will operate on Localhost listen = 127.0.0.1 service imap { inet_listener imap-login { port = 143 } # inet_listener imaps { # port = 993 # ssl = yes # } } # mail_home is only for virtual users # A virtual user is a user with no system account # I have no virtual users, so I've commented out mail_home. #mail_home = /srv/mail/%{user} # mail_driver is the storage format mail_driver = maildir # mail_path is location of top of storage data # WARNING: For troubleshooting be prepared to switch # to literal location of ~ mail_path = ~/mail/Maildir # In my case # mail_home is the home directory of the user identified as ~ # WARNING: system users have no ~ without it. mail_home = /home/slitt # You need a log you can locate # There might not be a log_path=/var/log/dovecot.log #mail_uid = slitt #mail_gid = slitt mail_uid = vmail mail_gid = vmail # By default first_valid_uid is 500. #If your vmail user's UID is smaller, # you need to modify this: #first_valid_uid = uid-number-of-vmail-user namespace inbox { inbox = yes separator = / } # Authenticate as system users: passdb pam { driver = pam #driver = passwd } userdb passwd { driver = passwd } #ssl_server_cert_file = /etc/dovecot/ssl-cert.pem #ssl_server_key_file = /etc/dovecot/ssl-key.pem =============================================== The following is the output of dovecot -n: =============================================== # 2.4.2 (0962ed2104): /etc/dovecot/dovecot.conf # OS: Linux 6.12.71_1 x86_64 # Hostname: dovecotvoid dovecot_config_version = 2.4.2 dovecot_storage_version = 2.4.2 listen = 127.0.0.1 log_path = /var/log/dovecot.log mail_driver = maildir mail_gid = vmail mail_home = /home/slitt mail_path = ~/mail/Maildir mail_uid = vmail protocols { imap = yes lmtp = no pop3 = no } service imap { inet_listener imap-login { port = 143 } } namespace inbox { inbox = yes separator = / } passdb pam { driver = pam } userdb passwd { driver = passwd } ===============================================

5 5

Republish of 2.4.2
by Aki Tuomi 10 Mar '26

10 Mar '26

Hi all! We have republished 2.4.2 packages to fix some packaging issues with Pigeonhole. Please note that for now dovecot-sieve and dovecot-managesieved will get installed together due to dependency issues. Kind regards, Aki Tuomi

1 0

solr-config-9.xml Fails to Load with Solr 9.10.1
by Steven Smith 10 Mar '26

10 Mar '26

I’m trying to use the latest dovecot solr module solr-config-9.xml at with Solr 9.10.1: https://github.com/dovecot/core/blob/956fd0f9a101673be72a7df7d643dd20cf4c40… This dovecot module has been updated to work with version 9.8 and removes the deprecated <lib> directives. However, I observe that it does not load under solr 9.10.1 with the Java exception below. Does anyone have any pointers on how to modify this module for the latest solr versions? var/solr/logs/solr-8983-console.log: > 2026-03-10 01:34:45.983 INFO (main) [] o.a.s.c.CorePropertiesLocator Found 1 core definitions underneath /opt/local/var/solr > 2026-03-10 01:34:45.984 INFO (main) [] o.a.s.c.CorePropertiesLocator Cores are: [dovecot] > 2026-03-10 01:34:46.012 INFO (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.c.SolrConfig Using Lucene MatchVersion: 9.8.0 > 2026-03-10 01:34:46.045 INFO (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.s.ManagedIndexSchemaFactory The schema is configured as managed, but managed schema resource managed-schema.xml not found - loading non-managed schema schema.xml instead > 2026-03-10 01:34:46.064 INFO (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.s.IndexSchema Schema name=dovecot > 2026-03-10 01:34:46.100 ERROR (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.c.CoreContainer SolrCore failed to load on startup =>org.apache.solr.common.SolrException: Unable to create core [dovecot] > at org.apache.solr.core.CoreContainer.createFromDescriptor(CoreContainer.java:1803) I'm trying to use the latest dovecot solr module solr-config-9.xml at with Solr 9.10.1: [1]https://github.com/dovecot/core/blob/956fd0f9a101673be72a7df7d643dd20cf4c… This dovecot module has been updated to work with version 9.8 and removes the deprecated <lib> directives. However, I observe that it does not load under solr 9.10.1 with the Java exception below. Does anyone have any pointers on how to modify this module for the latest solr versions? var/solr/logs/solr-8983-console.log: 2026-03-10 01:34:45.983 INFO (main) [] o.a.s.c.CorePropertiesLocator Found 1 core definitions underneath /opt/local/var/solr 2026-03-10 01:34:45.984 INFO (main) [] o.a.s.c.CorePropertiesLocator Cores are: [dovecot] 2026-03-10 01:34:46.012 INFO (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.c.SolrConfig Using Lucene MatchVersion: 9.8.0 2026-03-10 01:34:46.045 INFO (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.s.ManagedIndexSchemaFactory The schema is configured as managed, but managed schema resource managed-schema.xml not found - loading non-managed schema schema.xml instead 2026-03-10 01:34:46.064 INFO (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.s.IndexSchema Schema name=dovecot 2026-03-10 01:34:46.100 ERROR (coreLoadExecutor-13-thread-1) [ x:dovecot] o.a.s.c.CoreContainer SolrCore failed to load on startup =>org.apache.solr.common.SolrException: Unable to create core [dovecot] at org.apache.solr.core.CoreContainer.createFromDescriptor(CoreContainer.java:1803) References Visible links 1. https://github.com/dovecot/core/blob/956fd0f9a101673be72a7df7d643dd20cf4c40…

1 1

Preventing Plain Auth
by Steve Litt 10 Mar '26

10 Mar '26

Hi all, https://doc.dovecot.org/2.4.2/core/summaries/settings.html , the auth_allow_cleartext section, says "If no, disables the LOGIN command and all other cleartext authentication unless SSL/TLS is used (LOGINDISABLED capability) or the connection is secured (see ssl). See SSL configuration for more detailed explanation of how this setting interacts with the ssl setting. This setting replaces the disable_plaintext_auth setting." I put auth_allow_cleartext = no in my 2.4.2 dovecot.conf, but my Claws-Mail client can still access it, even though there are no key files. I tried putting this setting in several different places: Didn't prevent plain access. I tried switching from 127.0.0.1 to 10.0.2.15, same problem. The following is the output of my dovecot -n command: ========================================= # 2.4.2 (0962ed2104): /etc/dovecot/dovecot.conf # OS: Linux 6.12.74_1 x86_64 # Hostname: dovecotvoid dovecot_config_version = 2.4.2 dovecot_storage_version = 2.4.2 listen = 10.0.2.15 log_path = /var/log/dovecot.log mail_driver = maildir mail_gid = vmail mail_home = /home/slitt mail_path = ~/mail/Maildir mail_uid = vmail protocols { imap = yes lmtp = no pop3 = no } service imap { inet_listener imap-login { auth_allow_cleartext = no } } namespace inbox { inbox = yes separator = / } passdb pam { driver = pam } userdb passwd { driver = passwd } ========================================= How do I disable plain text authentication? Thanks, SteveT Steve Litt http://444domains.com

4 13