- dovecot - dovecot.org

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

2 3

[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

2 3

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

2 1

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 02 Apr '26

02 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 01 Apr '26

01 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

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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

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[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

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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

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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

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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?

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