This update for dovecot23 fixes the following issues: Security issues fixed: - CVE-2020-12100: Fixed a resource exhaustion caused by deeply nested MIME parts . - CVE-2020-24386: Fixed an issue with IMAP hibernation that allowed users to access other users" emails . - CVE-2020-25275: Fixed a crash when the 10000th MIME part was message/rfc822 . Non-security issues fixed: - Pigeonhole was updated to version 0.5.11. - Dovecot was updated to version 2.3.11.3.