N/A - USN-3881-1

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

- Ubuntu 18.10 - Ubuntu 18.04 LTS - Ubuntu 16.04 LTS - Ubuntu 14.04 LTS

Summary:

Dovecot could be made to expose sensitive information over the network.

Software Description: - dovecot: IMAP and POP3 email server

Details:

It was discovered that Dovecot incorrectly handled client certificates. A remote attacker in possession of a valid certificate with an empty username field could possibly use this issue to impersonate other users.

Update instructions:

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

Ubuntu 18.10:
dovecot-core 1:2.3.2.1-1ubuntu3.1

Ubuntu 18.04 LTS:
dovecot-core 1:2.2.33.2-1ubuntu4.2

Ubuntu 16.04 LTS:
dovecot-core 1:2.2.22-1ubuntu2.9

Ubuntu 14.04 LTS:
dovecot-core 1:2.2.9-1ubuntu2.5

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

References:
https://usn.ubuntu.com/usn/usn-3881-1
CVE-2019-3814

Package Information:
https://launchpad.net/ubuntu/+source/dovecot/1:2.3.2.1-1ubuntu3.1
https://launchpad.net/ubuntu/+source/dovecot/1:2.2.33.2-1ubuntu4.2
https://launchpad.net/ubuntu/+source/dovecot/1:2.2.22-1ubuntu2.9
https://launchpad.net/ubuntu/+source/dovecot/1:2.2.9-1ubuntu2.5