USN-3258-2: Dovecot regression

Publication date

11 April 2017

Overview

USN-3258-1 introduced a regression in Dovecot.


Packages

  • dovecot - IMAP and POP3 email server

Details

USN-3258-1 intended to fix a vulnerability in Dovecot. Further investigation
revealed that only Dovecot versions 2.2.26 and newer were affected by the
vulnerability. Additionally, the change introduced a regression when Dovecot
was configured to use the "dict" authentication database. This update reverts
the change. We apologize for the inconvenience.

Original advisory details:

It was discovered that Dovecot incorrectly handled some usernames. An attacker
could possibly use this issue to cause Dovecot to hang or crash, resulting in a
denial of service.

USN-3258-1 intended to fix a vulnerability in Dovecot. Further investigation
revealed that only Dovecot versions 2.2.26 and newer were affected by the
vulnerability. Additionally, the change introduced a regression when Dovecot
was configured to use the "dict" authentication database. This update reverts
the change. We apologize for the inconvenience.

Original advisory details:

It was discovered that Dovecot incorrectly handled some usernames. An attacker
could possibly use this issue to cause Dovecot to hang or crash, resulting in a
denial of service.

Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
16.10 yakkety dovecot-core –  1:2.2.24-1ubuntu1.3
16.04 xenial dovecot-core –  1:2.2.22-1ubuntu2.4

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