- dovecot - dovecot.org

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 |

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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."

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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

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Issues with 2.4.1 & remote postgresql server
by Terry Braun 14 Mar '26

14 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

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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 } ===============================================

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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

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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

[BUG?] Dovecot 2.4.2 from Dovecot repo (RHEL 9) does not implement Sieve (properly/fully)
by Patrick S 09 Mar '26

09 Mar '26

Hi all Below is report of what I suspect is a bug arising in Dovecot 2.4.x regarding Sieve functionality after Pigeonhole functionality was folded into Dovecot/Dovecot-sieve. ISSUE: ====== I am building a new mail server on Rocky Linux 9.7 with Postfix 3.10 and Dovecot 2.4.2. The base installation & setup of Dovecot was OK with core functionality (Postfix interoperability and mail into virtual mail domain mailboxes no problem). Once I had the base setup done I started with Sieve functionality: 1) Incoming mail marked as SPAM by Rspamd auto moved into /Junk 2) Mail manually moved in/out of /Junk handed to Rspamd for training as SPAM/HAM This consistantly failed - the first issue I found was Dovecot failing to restart and `dovecot -n` reporting fatal errors related to sieve — section not found etc. etc. From my reading previously I knew I needed to install `dovecot-sieve` and it was installed before I started working on Sieve functionality. I also saw `dovecot-pigeonhole` but I seemed to read that (version >= 2.4) the functionality for that had been included in `dovecot-sieve` **and** there was no Pigeonhole included in the Dovecot 2.4.2 repo — also if I tried to install it I got errors of course because of the version mismatch, and it was not in the dovecot-2.4-latest repo. ``` # dnf info dovecot-pigeonhole Last metadata expiration check: 1:21:15 ago on Fri 06 Mar 2026 08:05:08. Available Packages Name : dovecot-pigeonhole Epoch : 1 Version : 2.3.16 Release : 15.el9 Architecture : x86_64 Size : 371 k Source : dovecot-2.3.16-15.el9.src.rpm Repository : appstream Summary : Sieve and managesieve plug-in for dovecot URL : https://www.dovecot.org/ License : MIT and LGPLv2 Description : This package provides sieve and managesieve plug-in for dovecot LDA. ``` I also saw `dovecot-managesieved` but as I was **not** going to implement a client sieve functionality I did not install that. Anyway I could not even get to first base with Sieve, Dovecot simply did not know about it. I went on IRC and chatted with Aki Tuomi who confirmed that "yeah, looks like there is some packaging mistake." because the directory `/usr/lib64/dovecot/settings` was empty. As a workaround he suggested "you need to install dovecot-managesieved as workaround". I did that and as a result the following files appeared: ``` -rwxr-xr-x 1 root root 15560 Jan 8 12:13 libmanagesieve_login_settings.so -rwxr-xr-x 1 root root 15840 Jan 8 12:13 libmanagesieve_settings.so -rwxr-xr-x 1 root root 19656 Jan 8 12:13 libpigeonhole_settings.so ``` The `dovecot -n` errors went away, it recognised the sieve directives, and I continued with the Sieve setup. All — `dovecot.conf`, sieve files source and compiled — installed OK. But the sieve functionality simply refused to work. I got advice and we found the following which essentially points to sieve (even with `dovecot-managesieved` installed) not working. After installing everything — dovecot.conf, sieve files (compiled successfully) and a pipe to a shell script to call `rspamc` nothing seemed to happen. * `journalctl -f -u dovecot | grep -E "sieve|pipe"` -> nothing showed * `rspamc stat` -> 'Messages scanned' & 'Messages learned' no increase When we checked we found the following: 1) `lib90_sieve_settings.so` (which should be in `/etc/lib64/dovecot/settings`) is missing from the system. `find / -name "lib90_sieve_settings.so"` -> not found I believe the file is critical for the running of (Dovecot using) Sieve? 2) The Dovecot build options missing any sieve functionality: ``` #dovecot --build-options Build options: ioloop=epoll notify=inotify openssl io_block_size=8192 SQL driver plugins: mysql postgresql sqlite Passdb: ldap pam passwd passwd-file sql Userdb: ldap(plugin) passwd prefetch passwd-file sql ``` I believe (I was told) that minus the above (even though `dovecot-managesieved` was installed as well as `dovecot-sieve`) Sieve simply will not function. Is this a bug/packaging error? Regards Patrick ENVIRONMENT: ============ Software -------- * Rocky Linux 9.7 (RHEL) * Postfix 3.10 Built from source * Postscreen running in Postfix * Dovecot 2.4 installed from Dovecot repo * Valkey 9.0.3 (Redis replacement) * Rspamd 3.14.3 Setup ----- * Rspamd <-> Valkey communicate via Unix socket * Postfix & Dovecot <-> Rspamd via inet port/milter: smtpd_milters = inet:localhost:11332 non_smtpd_milters = inet:localhost:11332 * 'First line defence' = DNSBL via postscreen * Rspamd SPF checking, DKIM signing and DMARC configured All of the above installed, working and tested. DOVECOT PACKAGES INSTALLED: =========================== ``` Name : dovecot Version : 2.4.2 Architecture : x86_64 Source : dovecot-2.4.2-2.src.rpm From repo : dovecot-2.4-latest Name : dovecot-sieve Version : 2.4.2 Architecture : x86_64 Source : dovecot-sieve-2.4.2-2.src.rpm From repo : dovecot-2.4-latest Name : dovecot-managesieved (see note about this in the email) Version : 2.4.2 Architecture : x86_64 Source : dovecot-sieve-2.4.2-2.src.rpm From repo : dovecot-2.4-latest Name : dovecot-submissiond Version : 2.4.2 Architecture : x86_64 Source : dovecot-2.4.2-2.src.rpm From repo : dovecot-2.4-latest Name : dovecot-imapd Version : 2.4.2 Architecture : x86_64 Source : dovecot-2.4.2-2.src.rpm From repo : dovecot-2.4-latest Name : dovecot-lmtpd Version : 2.4.2 Architecture : x86_64 Source : dovecot-2.4.2-2.src.rpm From repo : dovecot-2.4-latest Name : dovecot-lua Version : 2.4.2 Architecture : x86_64 Source : dovecot-2.4.2-2.src.rpm From repo : dovecot-2.4-latest ``` OUTPUT OF `dovecot -n`: ======================= ``` # dovecot -n # 2.4.2-2 (0962ed2104): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.2-2 (767418c3) # OS: Linux 5.14.0-611.34.1.el9_7.x86_64 x86_64 Rocky Linux release 9.7 (Blue Onyx) # Hostname: srv01.example.com dovecot_config_version = 2.4.2 auth_default_domain = example.com auth_mechanisms = plain auth_username_format = %{user | lower } dovecot_storage_version = 2.4.2 mail_access_groups = vmail mail_control_path = ~/control mail_driver = maildir mail_gid = 5000 mail_home = /var/vmail/%{user | domain }/%{user | username } mail_index_path = ~/indexes mail_path = %{home}/Maildir mail_privileged_group = vmail mail_uid = 5000 mailbox_list_utf8 = yes protocols = imap lmtp sieve_global_extensions { vnd.dovecot.pipe = yes } sieve_pipe_bin_dir = /etc/dovecot/sieve/bin sieve_plugins { sieve_imapsieve = yes sieve_extprograms = yes } sieve_trace_dir = /var/log/dovecot/sieve-trace sieve_trace_level = actions ssl = required syslog_facility = local5 protocol lmtp { mail_plugins { sieve = yes } } ssl_server { cert_file = /etc/ssl/server/server_example_com.crt key_file = /etc/ssl/server/server_example_com.key } passdb passwd-file { auth_username_format = %{user | username} default_password_scheme = SHA512-CRYPT passwd_file_path = /etc/dovecot/passwd } userdb passwd-file { auth_username_format = %{user | username} passwd_file_path = /etc/dovecot/passwd fields { gid:default = 5000 uid:default = 5000 } } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } service imap-login { inet_listener imap { port = 0 } inet_listener imaps { port = 993 ssl = yes } } service auth-worker { user = $SET:default_internal_user } service anvil { unix_listener anvil { group = $SET:default_internal_group mode = 0660 } } service doveadm { unix_listener doveadm-server { mode = 0600 user = $SET:default_internal_user } } sieve_script rspamd_to_junk { driver = file path = /etc/dovecot/sieve/rspamd-to-junk.sieve type = before } namespace inbox { mail_plugins { imap_sieve = yes } inbox = yes mailbox Junk { auto = create autoexpunge = 90d special_use = "\\Junk" sieve_script report-spam { cause = copy path = /etc/dovecot/sieve/report-spam.sieve type = before } } imapsieve_from Junk { sieve_script report-ham { cause = copy path = /etc/dovecot/sieve/report-ham.sieve type = before } } mailbox Drafts { auto = subscribe special_use = "\\Drafts" } mailbox Sent { auto = subscribe special_use = "\\Sent" } mailbox Trash { auto = subscribe special_use = "\\Trash" } } ```

4 7

Curve25519/Ed25519 ?
by Steve Litt 09 Mar '26

09 Mar '26

On my new Dovecot 2.4.2 IMAP server, which when completed will be accessible only via SSL, I plan to use Curve25519/Ed25519 self-signed-cert/private-key. Is there any reason this would be a mistake? Thanks, SteveT Steve Litt http://444domains.com

2 2

Dovecot 2.4 doveadm_worker_count corrupts tab-formatted output
by Philip Iezzi 08 Mar '26

08 Mar '26

Hi there On a Dovecot 2.4.2 (Debian Bookworm) server with over 1300 users, I am using the following config to retrieve quota usage information with doveadm: --------------------------------------- quota "User quota" { } mail_plugins = quota acl mail_log notify userdb sql { iterate_query = SELECT username AS user, CONCAT(quota, 'M') AS quota_storage_size FROM mailaccounts WHERE active = 1 query = \ SELECT '/var/vmail/%{user | domain}/%{user | username}' AS home, 'vmail' AS uid, 'vmail' AS gid, CONCAT(quota, 'M') AS quota_storage_size \ FROM mailaccounts \ WHERE username = '%{user}' AND (active = 1 OR transport_suspended = 0) } --------------------------------------- Initially, I had to run `doveadm quota recalc -A` to recalc quotas and populate the `count` quota driver which is enabled by default for "User quota". But still, it took roughly 20ms per single user or 15-20s for all users: $ time doveadm -f tab quota get -u demo(a)example.com real 0m0.020s $ time doveadm -f tab quota get -A real 0m16.800s Now, to greatly speed this up, I have introduced parallel processing: doveadm_worker_count = 4 Like this, `doveadm -f tab quota get -A` runs approx 10x faster, done in 1.5 - 2.5s But there is one major drawback which I assume to be a bug: # sane output without `doveadm_worker_count = 4` => always 6 fields demo(a)example.com User quota STORAGE 29 204800 0 demo(a)example.com User quota MESSAGE 1 - 0 # broken output with `doveadm_worker_count = 4` => sometimes 7 fields demo(a)example.com User quota STORAGE 29 2048 00 0 demo(a)example.com User quota MESSAGE 1 - 0 Somehow, the tab formatter does not play nicely together with parallel processing. On some output, the value gets split apart by an extra tab, e.g. '2024<TAB>00' in above example. Can you explain this corrupted data? Some kind of "output interleaving" seems to happen when running parallel workers. If I switch to json output (`doveadm -f json quota get -A`), this does not seem to happen and I always get valid JSON output, even with `doveadm_worker_count = 4`. Cheers, Philip

2 8

Getting quota limits from DB
by Alberto 04 Mar '26

04 Mar '26

Hi group: I have a Docker Dovecot 2.4.2 installation with MySQL user management, with this record: SELECT * FROM users; +---------------------------------------------------------------------------- | username | domain | password | home | uid | gid | active | quota | quotamsgs | crampassword +---------------------------------------------------------------------------- | alberto | bersol.info | {MD5-CRYPT}$1$Jm... | /var/mail/alberto | 1000 | 1000 | Y | 3221225472 | 149999 | {CRAM-MD5}fd246... | +---------------------------------------------------------------------------- But I have a problem with user quota definitions... If I run "doveadm" command, I get the user quota occupation, I have "quota_clone" plugin working, but I don't get user quota limit, I don't know why: ----- # docker exec -it midovecot doveadm quota get -A Username Quota name Type Value Limit % alberto(a)bersol.info User quota STORAGE 1925805 3145728 61 alberto(a)bersol.info User quota MESSAGE 37608 100000 37 ----- That limit isn't the correct limit set in DB, but the one is put in the config, and it must to be override in my userdb:Extra Fields. ----- # # docker exec -it midovecot doveadm config # 2.4.2 (0962ed2104): /etc/dovecot/dovecot.conf ... userdb sql { iterate_query = SELECT CONCAT(username,'@',domain) AS user FROM users query = SELECT home,CONCAT(username,'@',domain) AS username,crampassword AS password,uid AS userdb_uid,gid AS userdb_gid,CONCAT(quota,'B') AS userdb_quota_storage_size,concat('*:messages=',quotamsgs) AS userdb_quota_storage_size FROM users WHERE username = '%{ user | username | lower }' AND domain = '%{ user | domain | lower }' } ... quota_storage_size = 3G quota_message_count = 100000 ... ----- Do you have any idea of the problem? Best Regards, Alberto

2 3

Dovecot marking outgonig emails as unread
by stef204 03 Mar '26

03 Mar '26

Starting a few days ago, I have one email account where ALL outgoing emails are automatically marked as UNREAD. The message is sent, then copied to the "Sent" folder, and has status "unread". Then, a couple of minutes later, something happens where this message gets marked as UNREAD, without ANY interaction of client side. This occurs not matter the email client used, I have tried it with multiple email clients, both local and via web interface, the behavior does not change. This is via Dovevot on Cpanel. if I look at the [1]changelog, it is difficult to identify which changes could have triggered this as there seem to be changes impacting Dovecot almost with every update. I do not control the server myself, this is on a shared hosting plan; tech support has been willing to troubleshoot but is unable to locate the problem. This problem does NOT occur on other email accounts on the same domain, so it looks to me like some corruption or problem syncing flags perhaps? I am at a loss at the moment to fix this behavior. Any suggestions or ideas welcome. Thanks. References Visible links 1. https://docs.cpanel.net/changelogs/132-change-log/

3 5

[Pigeonhole] extracttext on "message/rfc822" attachment ignores included headers
by quentinduchemin＠tuta.io 03 Mar '26

03 Mar '26

Hi everyone! I'm not sure this is a design decision, a bug, something not implemented or malformed input on my side. My use case is the following: users that forward their mails outside the domain I manage have the option to report spam as attachment so the spam classifier can learn anyway. I prefer attachment over forward because MUAs have their own way to do it and it's difficult to reliably reconstruct some headers/email structure that can be important for the spam classifier. Each input message is processed through a Sieve extensions of RFC 5703 to extract the attachment. I ask user to produce a file with .eml extension through any export-like feature of their MUA. Below is an example EML file produced by Tuta (Thunderbird does a similar thing with a different encoding for the body). I'll use a bunch of = characters as a separator in the rest of this. =============================================== [...bunch of header...] X-MS-Exchange-CrossTenant-rms-persistedconsumerorg: 00000000-0000-0000-0000-0000000000 00 X-MS-Exchange-Transport-CrossTenantHeadersStamped: TYSPR04MB7035 Content-Type: multipart/related; boundary="------------79Bu5A16qPEYcVIZL@tutanota" --------------79Bu5A16qPEYcVIZL@tutanota Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: base64 DQo8ZGl2IHN0eWxlPSJmb250LWZhbWlseTogQXB0b3MsIEFwdG9zX0VtYmVkZGVkRm9udCwgQXB0b3 NfTVNGb250U2VydmljZSwgQ2FsaWJyaSwgSGVsdmV0aWNhLCBzYW5zLXNlcmlmOyBmb250LXNpemU6 [...base64 encoding of the body...] =============================================== While attached and sent, the received messaged looks like this: =============================================== [...headers of the actual email...] X-Infomaniak-Routing: alpha This is a multi-part message in MIME format. --------------5jyKrhQ08xXUif7LHhgg648N Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit --------------5jyKrhQ08xXUif7LHhgg648N Content-Type: message/rfc822; name="a.eml" Content-Disposition: attachment; filename="a.eml" Content-Transfer-Encoding: 7bit [...headers of the spam....] Subject: Re: //Re: AI + Ranking /// Thread-Topic: //Re: AI + Ranking /// [....] Content-Type: multipart/related; boundary="------------79Bu5A16qPEYcVIZL@tutanota" --------------79Bu5A16qPEYcVIZL@tutanota Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: base64 DQo8ZGl2IHN0eWxlPSJmb250LWZhbWlseTogQXB0b3MsIEFwdG9zX0VtYmVkZGVkRm9udCwgQXB0b3 NfTVNGb250U2VydmljZSwgQ2FsaWJyaSwgSGVsdmV0aWNhLCBzYW5zLXNlcmlmOyBmb250LXNpemU6 [...base64 encoding of the spam....] --------------79Bu5A16qPEYcVIZL@tutanota-- --------------5jyKrhQ08xXUif7LHhgg648N-- =============================================== I face two issues: 1. Only the base64 decoded string can be retrived through foreverypart/extracttext; 2. It has a lot of newlines. - 2. is not a big deal. The original spam has a lot of HTML junk, and each line with HTML without an inner text node is stripped, but the newline is kept. I don't know if this is intended. - 1. is more of a big deal. To try to confirm that, I made an over-simplified version of the Sieve script (I skip configuration but plugins are loaded etc, please ask if useful). =============================================== [...require...] foreverypart { extracttext "eml"; debug_log "PART ============================== ${eml}"; } =============================================== mail_debug is activated. In the logs, I can read: =============================================== Info: sieve: DEBUG: PART ============================== Info: sieve: DEBUG: PART ============================== Info: sieve: DEBUG: PART ============================== Info: sieve: DEBUG: PART ============================== Info: sieve: DEBUG: PART ============================== Info: sieve: Info: sieve: Info: sieve: Info: sieve: Info: sieve: Info: sieve: Info: sieve: Hello, Info: sieve: Info: sieve: Hope you're doing well. Info: sieve: Info: sieve: Info: sieve: Info: sieve: Info: sieve: Would you like attract more traffic with our AEO + GEO + SEO services. AI-driven search is here—don’t miss out. =============================================== So multiple parts are analyzed but only the last gives something. The RFC says that "If the transfer encoding or character set is unrecognized by the implementation or recognized but invalid, an empty string will result.". But it's over my knowledge. I activated trace for Sieve with "matching" level, and the file looks like (this is another test but was the same result): =============================================== Sieve trace log for message delivery: Username: REDACTED Session ID: ozNMOEPNl2nlAAAAO14Lzw Sender: REDACTED Final recipient: REDACTED Default mailbox: INBOX ## Started executing script 'move-spam' 33: foreverypart loop begin 33: loop ends at line 36 35: extracttext command 36: assign 'eml' [0] = "" 36: debug_log "PART ============================== " 36: foreverypart loop end 36: switched to next message part 36: looping back to line 35 35: extracttext command 36: assign 'eml' [0] = "" 36: debug_log "PART ============================== " 36: foreverypart loop end 36: switched to next message part 36: looping back to line 35 35: extracttext command 36: assign 'eml' [0] = "" 36: debug_log "PART ============================== " 36: foreverypart loop end 36: switched to next message part 36: looping back to line 35 35: extracttext command 36: assign 'eml' [0] = "" 36: debug_log "PART ============================== " 36: foreverypart loop end 36: switched to next message part 36: looping back to line 35 35: extracttext command 36: assign 'eml' [0] = "Hi, Just checking in to see if you had a chance to review my earlier message. [...body spam....] 36: debug_log "PART ============================== ????????????Hi, ?? ??Just checking in t..." 36: foreverypart loop end 36: no more message parts 36: exiting loops at line 36 ## Finished executing script 'move-spam' =============================================== Hypothesis: A. Could it be because the mail headers are indistinguishable from the part headers? B. Or is it related to Pigeonhole not implementing yet the enclose extension, which do this the other way? I hope this message is not too hard to read with all the code/logs. Please tell me if there is a better way of doing it. And thanks in advance for any help, because I don't really know what to do and trying to take a (superficial) look at the Pigeonhole code didn't helped.

1 2

Panic: file imap-sieve-storage.c: line 216 (imap_sieve_add_mailbox_event): assertion failed: (ismt->src_box == NULL || ismt->src_box == src_box)
by Christian Kivalo 28 Feb '26

28 Feb '26

Reposting my reply from a few days ago to a thread with the same panic message. I found this in my logs when some mails that got deleted on the phone were still visible in roundcube. I currently have three users that trigger the panic. One user with an iPad accounts for nearly all of the panics. The problem shows when the account is accessed from android (thunderbird) or ipad. The same accounts show no problems when beeing used with roundcube or thunderbird on windows. I enabled core dumps on 2026-01-14 and have ~8500 core dumps of the imap binary until now. What causes this error and how can I fix it? In the logs all I see is the users login, then the panic. # doveconf -n # 2.4.2-2+debian13 (0962ed2104): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.2-2+debian13 (767418c3) # OS: Linux 6.12.0-custom.kvm x86_64 Debian 13.3 ext4 2026-01-13T21:44:32.317609+01:00 uschi dovecot: imap-login: Logged in: user=<user(a)example.com>, method=PLAIN, rip=<IP1>, lip=<IP2>, mpid=4194077, TLS, session=<cpkID0tId7dUc9rl> 2026-01-13T21:44:38.455379+01:00 uschi dovecot: imap(user(a)example.com)<4194077><cpkID0tId7dUc9rl>: Panic: file imap-sieve-storage.c: line 216 (imap_sieve_add_mailbox_event): assertion failed: (ismt->src_box == NULL || ismt->src_box == src_box) 2026-01-13T21:44:38.458755+01:00 uschi dovecot: imap(user(a)example.com)<4194077><cpkID0tId7dUc9rl>: Error: Raw backtrace: #1 [unw_get_proc_name() failed: -10] -> #2 [unw_get_proc_name() failed: -10] -> #3 i_panic[0x7f6b6c46c2f6] -> #4 [unw_get_proc_name() failed: -10] -> #5 [unw_get_proc_name() failed: -10] -> #6 [unw_get_proc_name() failed: -10] -> #7 mailbox_save_alloc[0x7f6b6ca103c0] -> #8 [unw_get_proc_name() failed: -10] -> #9 command_exec[0x55654e677400] -> #10 [unw_get_proc_name() failed: -10] -> #11 [unw_get_proc_name() failed: -10] -> #12 [unw_get_proc_name() failed: -10] -> #13 client_handle_input[0x55654e67ddc0] -> #14 client_continue_pending_input[0x55654e67e0b0] -> #15 io_loop_call_io[0x7f6b6c565490] -> #16 io_loop_handler_run_internal[0x7f6b6c567230] -> #17 io_loop_handler_run[0x7f6b6c5673c0] -> #18 io_loop_run[0x7f6b6c5675a0] -> #19 master_service_run[0x7f6b6c4b27f0] -> #20 main[0x55654e6688a0] -> #21 [unw_get_proc_name() failed: -10] -> #22 __libc_start_main[0x7f6b6c234ce0] -> #23 _start[0x55654e668eb0] 2026-01-13T21:44:38.459536+01:00 uschi dovecot: imap(user(a)example.com)<4194077><cpkID0tId7dUc9rl>: Fatal: master: service(imap): child 4194077 killed with signal 6 (core dumps disabled - https://dovecot.org/bugreport.html#coredumps) # coredumpctl dump PID: 1071230 (imap) UID: 5000 (vmail) GID: 5000 (vmail) Signal: 6 (ABRT) Timestamp: Fri 2026-01-16 19:17:15 CET (2s ago) Command Line: $'dovecot/imap [user(a)example.com <IP redacted> UID MOVE]' Executable: /usr/lib/dovecot/imap Control Group: /system.slice/dovecot.service Unit: dovecot.service Slice: system.slice Boot ID: 3668d179bda340229a780d5d43e426c3 Machine ID: 05698baa30ae984c9bd014566e16da18 Hostname: uschi Storage: /var/lib/systemd/coredump/core.imap.5000.3668d179bda340229a780d5d43e426c3.1071230.1768587435000000.zst (present) Size on Disk: 1.1M Message: Process 1071230 (imap) of user 5000 dumped core. Module libgcc_s.so.1 from deb gcc-14-14.2.0-19.amd64 Module libstdc++.so.6 from deb gcc-14-14.2.0-19.amd64 Module libzstd.so.1 from deb libzstd-1.5.7+dfsg-1.amd64 Stack trace of thread 1071230: #0 0x00007fbd1ca9f95c n/a (libc.so.6 + 0x9495c) #1 0x00007fbd1ca4acc2 raise (libc.so.6 + 0x3fcc2) #2 0x00007fbd1ca334ac abort (libc.so.6 + 0x284ac) #3 0x00007fbd1cc6caa0 n/a (libdovecot.so.0 + 0x6caa0) #4 0x00007fbd1cd49e67 n/a (libdovecot.so.0 + 0x149e67) #5 0x00007fbd1cc6c3d0 i_panic (libdovecot.so.0 + 0x6c3d0) #6 0x00007fbd1c42f942 n/a (lib95_imap_sieve_plugin.so + 0x4942) #7 0x00007fbd1c431223 n/a (lib95_imap_sieve_plugin.so + 0x6223) #8 0x00007fbd1d258f10 n/a (libdovecot-storage.so.0 + 0x11bf10) #9 0x00007fbd1d1a843b mailbox_save_alloc (libdovecot-storage.so.0 + 0x6b43b) #10 0x00005590b7ed4a69 n/a (n/a + 0x0) ELF object binary architecture: AMD x86-64 -- Christian Kivalo

5 12

LDAP AD Quota override not working
by wt.forsaken＠gmail.com 26 Feb '26

26 Feb '26

Hi there, I'm testing the new version of Dovecot 2.4 in Debian 13 before upgrading to my customers and I'm having difficult on trying to override the user's quota. The LDAP base is from Samba4 AD and having been trying the following configuration: auth-ldap.conf.ext: ldap_uris = ldap://localhost ldap_auth_dn = cn=admin,dc=localdomain ldap_auth_dn_password = password ldap_base = ou=users, dc=localdomain passdb ldap { filter = (&(objectClass=person)(sAMAccountName=%{user})) bind = yes fields { userdb_quota_storage_size = %{ldap:telephoneNumber}B } } userdb prefetch { driver = prefetch } userdb ldap { fields { quota_storage_size = %{ldap:telephoneNumber}B } } 90-quota.conf mail_plugins { quota = yes } quota "User quota" { } quota_storage_size = 40M Since there is no quotaBytes in Samba AD, I'm testing to map the telephoneNumber parameters to override the quota, also I'm just testing a 40M to see how it works. Roundcube webmail can see the quota being overriden in its inferior bar, but when I send an email to the user which is above the quota, the journal log inform "failed to store into mailbox 'INBOX': Quota exceeded (mailbox for user is full)". I don't know how to override the quota, since in passdb section I used the "userdb_" prefix but it is not being passed to userdb when I input the "doveadm user ..." command. I don't know if I have been clear in my request, but I'd appreciate any help.

3 3

Dovecot 2.4 LMTP socket for Postfix / Dovecot base_dir not created upon restart
by Philip Iezzi 24 Feb '26

24 Feb '26

Hi there, After over a week of Dovecot 2.3 -> 2.4 upgrade testing in various mailserver clones, I am now ready for the big picture. Thanks Aki for the Config Upgrader https://dovecot.org/upgrader/ which helped a lot! Tomorrow, I am planning to upgrade a larger mailserver in these 3 steps: 1) Debian Bullseye / Dovecot 2.3.21 => 2.4.1 2) Debian Bullseye => Bookworm / Dovecot 2.4.1 => 2.4.2 3) Debian Bookworm => Trixie Postfix needs to talk to Dovecot over LMTP, using the following in main.cf: virtual_transport = lmtp:unix:/run/dovecot/lmtp Now, while testing this in a full server clone, I stepped over my planned LMTP server setup: =============================================== service lmtp { unix_listener /run/dovecot/lmtp { mode = 0666 user = postfix group = postfix } } protocols = imap pop3 sieve lmtp =============================================== The socket needs to be owned by postfix:postfix for some (security) reasons, otherwise Postfix complains. That's why I cannot go with the default, as documented here: https://doc.dovecot.org/2.4.2/core/config/delivery/lmtp.html#lmtp-server > The UNIX listener on $base_dir/lmtp is enabled by default when protocols setting contains lmtp. But, when using an absolute path on unix_listener, upgrade step 2) Bullseye=>Bookworm breaks with: Processing triggers for dovecot-core (2:2.4.2-2+debian12) ... Job for dovecot.service failed because the control process exited with error code. (...) dovecot[34446]: master: Error: service(lmtp): Socket already exists: /var/run/dovecot/lmtp dovecot[34446]: master: Fatal: Failed to start listeners I then moved to `unix_listener lmtp`: service lmtp { unix_listener lmtp { mode = 0666 user = postfix group = postfix } } Bookworm upgrade (restarted from scratch with a fresh server clone) went through fine. But even after several dovecot.service restarts, the socket ended up in /run/lmtp without creating the /run/dovecot directory, and after a full system reboot, it was suddenly back where I have expected it: /run/dovecot/lmtp I never changed base_dir, which defaults to /var/run/dovecot/ So, here's my question: Is that really the recommended setup (using `inet_listener lmtp` instead of an absolute path) and how can I trust Dovecot to always create the socket in $base_dir/lmtp as documented? Are you guys aware of this issue or was it just me, a temporary hiccup on my just upgraded server? I just found this in mail.log: dovecot: master: Error: bind(/var/run/dovecot/lmtp) failed: No such file or directory dovecot: master: Error: service(lmtp): net_listen_unix(/var/run/dovecot/lmtp) failed: No such file or directory dovecot: master: Fatal: Failed to start listeners Again, this problem seems to have occurred both with `unix_listener /run/dovecot/lmtp` and `unix_listener lmtp` and only resolved after a full system reboot. Thanks, Philip

2 2

Migrating a mailbox from v2.2 to v2.4, production server to pre-production server.
by Mike 23 Feb '26

23 Feb '26

I'm migrating a mailbox from dovecot v2.2 to v2.4. Not that it matters, I'm also changing from mbox to Maildir. As an initial test I used this command: sudo doveadm sync -1D -u theuser -m amailbox remote:theuser@destination.com I received this error: Error: doveadm: Unexpected or incomplete option: -U After changing the dsync_remote_cmd to: dsync_remote_cmd = ssh -l%{login} %{host} doveadm dsync-server -u%u I was able to transfer the mailbox without issue. Before changing it, the setting on the source server was: dsync_remote_cmd = ssh -l%{login} %{host} doveadm dsync-server -u%u -U I'm interested to discover what the -U was intended for since I couldn't find specific documentation to its use. I'll accept that it was a legacy thing and removing it won't cause any unintended consequences...but I do still have that curiosity about what it was for. Additionally, the subscription status doesn't seem to flow to the new server. When checking the source server with: doveconf -d | grep subscriptions doveconf -n | grep subscriptions No value is returned...So I'm wondering if I need to specifically set subscriptions = yes in the source server to make this happen properly. Maybe this is an artifact of using sync -1? Thanks for any insight you may provide. Mike

1 0

Localhost Dovecot server without ssl?
by Steve Litt 23 Feb '26

23 Feb '26

Hi all, I'd like your opinions to add to my own opinion. Bottom line question: If I trust everybody with physical access to my Daily Driver Desktop (DDD) computer, my Dovecot IMAP runs on my DDD, I access my Dovecot IMAP *exclusively* from my DDD, and I trust everybody with physical access to my DDD (that would be my wife), then if I serve out IMAP on localhost (127.0.0.1), am I being unduly risky using plain text auth (port 143)? Details: I use a Dovecot IMAP server, on my DDD, specifically to hold all my email messages. Therefore, I can use any IMAP aware email client, interchangeably, to view every email I've received since April 2001. People whose emails are held by their email clients are "locked in" to their email client unless they convert their email data. I can switch between Evolution and Claws-Mail, because one of the two is always doing something stupid. Bottom line: I use Dovecot IMAP exclusively to hold my emails and folders. Graphical description below: ISP ---> My --------> procmail --> Dovecot IMAP fetchmail Maildir | | V email <--- Dovecot client IMAP server For the time being, I don't need to access my Dovecot IMAP from any computer except my DDD, and therefore, I can serve Dovecot IMAP on 127.0.0.1. So here's my question. Assuming (and I know this is a big assumption) I'm not worried about somebody gaining physical possession of my DDD, is there any reason not to use plain text to access this server? Thanks, SteveT Steve Litt http://444domains.com

2 1

Copies/duplicates of Dovecot indices
by Joseph Tam 23 Feb '26

23 Feb '26

In my setup, I put mail indices outside the user's mailbox locations (user mailboxs are NFS, indices stored local attached storage). I notice that sometimes, there are 2 sets of indices representing the same mailbox: one at top level, one underneath .imap/. (They usually appear in the latter.) For example, if I have the configuration (Dovcot version 3.2.21) mail_location = mbox:~/mail:INBOX=/nfs/mail/%n:INDEX=/cache/%n I see for a particular user [1] drwx------ 5 user group 512 Feb 22 21:56 /cache/user/box [2] drwxr-xr-x 5 user group 512 Feb 22 21:46 /cache/user/.imap/box cooresponding to their mailbox in ~user/mail/box. Each of these have the dovecot.* index files. If I delete [1], it comes back. The timestamps are close to each other so both sets are being used, possibly by different clients. Another quirky discovery is 2 /.imap/ folders beneath each other e.g. /cache/user/.imap/folder1/folder2/.imap/box/dovecot.index What determines which index pathname gets created or used? Joseph Tam <jtam.home(a)gmail.com>

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