N/A - USN-4110-3

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 19.04 - Ubuntu 18.04 LTS - Ubuntu 16.04 LTS

Summary:

USN-4110-1 introduced a regression in Dovecot.

Software Description: - dovecot: IMAP and POP3 email server

Details:

USN-4110-1 fixed a vulnerability in Dovecot. The update introduced a regression causing a wrong check. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Nick Roessler and Rafi Rubin discovered that Dovecot incorrectly
handled certain data. An attacker could possibly use this issue
to cause a denial of service or execute arbitrary code.

Update instructions:

The problem can be corrected by updating your system to the following package versions:

Ubuntu 19.04:
dovecot-core 1:2.3.4.1-1ubuntu2.4

Ubuntu 18.04 LTS:
dovecot-core 1:2.2.33.2-1ubuntu4.5

Ubuntu 16.04 LTS:
dovecot-core 1:2.2.22-1ubuntu2.12

In general, a standard system update will make all the necessary changes.

References:
https://usn.ubuntu.com/4110-3
https://usn.ubuntu.com/4110-1
CVE-2019-11500

Package Information:
https://launchpad.net/ubuntu/+source/dovecot/1:2.3.4.1-1ubuntu2.4
https://launchpad.net/ubuntu/+source/dovecot/1:2.2.33.2-1ubuntu4.5
https://launchpad.net/ubuntu/+source/dovecot/1:2.2.22-1ubuntu2.12