========================================================================== Ubuntu Security Notice USN-4674-1 January 04, 2021 dovecot vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 20.10 - Ubuntu 20.04 LTS - Ubuntu 18.04 LTS - Ubuntu 16.04 LTS Summary: Several security issues were fixed in Dovecot. Software Description: - dovecot: IMAP and POP3 email server Details: It was discovered that Dovecot incorrectly handled certain imap hibernation commands. A remote authenticated attacker could possibly use this issue to access other users' email. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, and Ubuntu 20.10. (CVE-2020-24386) Innokentii Sennovskiy discovered that Dovecot incorrectly handled MIME parsing. A remote attacker could possibly use this issue to cause Dovecot to crash, resulting in a denial of service. (CVE-2020-25275) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 20.10: dovecot-core 1:2.3.11.3+dfsg1-2ubuntu0.1 Ubuntu 20.04 LTS: dovecot-core 1:2.3.7.2-1ubuntu3.3 Ubuntu 18.04 LTS: dovecot-core 1:2.2.33.2-1ubuntu4.7 Ubuntu 16.04 LTS: dovecot-core 1:2.2.22-1ubuntu2.14 In general, a standard system update will make all the necessary changes. References: https://usn.ubuntu.com/4674-1 CVE-2020-24386, CVE-2020-25275 Package Information: https://launchpad.net/ubuntu/+source/dovecot/1:2.3.11.3+dfsg1-2ubuntu0.1 https://launchpad.net/ubuntu/+source/dovecot/1:2.3.7.2-1ubuntu3.3 https://launchpad.net/ubuntu/+source/dovecot/1:2.2.33.2-1ubuntu4.7 https://launchpad.net/ubuntu/+source/dovecot/1:2.2.22-1ubuntu2.14