Download Dovecot 2.2.27

Dovecot is a mail server with support for imap, pop3, ipv6, ssl and tls, and is partly under an MIT and partly under a Lgplv2.1 license. Maildir, mbox and the self-developed dbox format can be used to store mail messages. In addition, MTAs such as Postfix 2.3+ and Exim 4.64+ can perform their smtp authentication process at Dovecot without any intermediate steps. The developer has released version 2.2.27 with the following announcement:

v2.2.27 released

Note that the download URLs are now https with a certificate from Let’s Encrypt.

• dovecot.list.index.log rotation sizes/times were changed so that the .log file stays smaller and .log.2 is deleted sooner.
• Added mail_crypt plugin that allows encryption of stored emails. see
• stats: Global stats can be sent to Carbon server by setting stats_carbon_server=ip:port
• imap/pop3 proxy: If passdb returns proxy_not_trusted, don’t send ID/XCLIENT
• Added generic hash modifier for %variables: %{;rounds=,truncate=,salt=s>:field} Hash algorithm is any of the supported ones, eg md5, sha1, sha256. Also “pkcs5” is supported using SHA256. For example: %{sha256:user} or %{md5;truncate=32:user}.
• Added support for SHA3-256 and SHA3-512 hashes.
• config: Support DNS wildcards in local_name, eg local_name *.example.com { .. } matches anything.example.com, but not multiple.anything.example.com.
• config: Support multiple names in local_name, eg local_name “1.example.com 2.example.com” { .. }
• Fixed crash in auth process when auth-policy was configured and authentication was aborted/failed without a username set.
• director: If two users had different tags but the same hash, the users may have been redirected to the wrong tag’s hosts.
• Index files may have been thought incorrectly lost, causing “Missing middle file seq=..” to be logged and index rebuild. This happened more easily with IMAP hibernation enabled.
• Various fixes to restoring state correctly in un-hibernation.
• dovecot.index files were commonly 4 bytes per email too large. This is because 3 bytes per email were being wasted that could have been used for IMAP keywords.
• Various fixes to handle dovecot.list.index corruption better.
• lib-fts: Fixed assert crash in address tokenizer with specific input.
• Fixed assert-crash in HTML to text parsing with specific input (eg for FTS indexing or snippet generation)
• doveadm sync -1: Fixed handling mailbox GUID conflicts.
• sdbox, mdbox: Perform full index rebuild if corruption is detected inside lib-index, which runs index fsck.
• quota: Don’t skip quota checks when moving mails between different quota roots.
• search: Multiple sequence sets or UID sets in search parameters weren’t handled correctly. They were incorrectly merged together.