Ubuntu Security Notice 4674-1 - 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. 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. Various other issues were also addressed.
a6fb24566e34ca33892166efc08d56441a09b26e354fd4b998d65c1ffc7d4c66
==========================================================================
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