USN-4010-1: Exim vulnerability

5 June 2019

exim4 vulnerability

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

  • Ubuntu 18.10
  • Ubuntu 18.04 LTS


Exim could be made to run commands if it received specially crafted network traffic.

Software Description

  • exim4 - Exim is a mail transport agent


It was discovered that Exim incorrectly handled certain decoding operations. A remote attacker could possibly use this issue to execute arbitrary commands.

Update instructions

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

Ubuntu 18.10
exim4-daemon-heavy - 4.91-6ubuntu1.1
exim4-daemon-light - 4.91-6ubuntu1.1
Ubuntu 18.04 LTS
exim4-daemon-heavy - 4.90.1-1ubuntu1.2
exim4-daemon-light - 4.90.1-1ubuntu1.2

To update your system, please follow these instructions:

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