An Exim security update has been released for Ubuntu Linux 14.04 ESM, 16.04 ESM, 18.04 LTS, and 20.04 LTS.

USN-5574-1: Exim vulnerability

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Ubuntu Security Notice USN-5574-1
August 22, 2022

exim4 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

Summary:

Exim could be made to crash of execute arbitrary code if it
received a specially crafted input.

Software Description:
- exim4: Exim is a mail transport agent

Details:

It was discovered that Exim incorrectly handled certain inputs.
An attacker could possibly use this issue to cause a crash or
execute arbitrary code.

Update instructions:

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

Ubuntu 20.04 LTS:
exim4-base 4.93-13ubuntu1.6
exim4-daemon-heavy 4.93-13ubuntu1.6
exim4-daemon-light 4.93-13ubuntu1.6

Ubuntu 18.04 LTS:
exim4-base 4.90.1-1ubuntu1.9
exim4-daemon-heavy 4.90.1-1ubuntu1.9
exim4-daemon-light 4.90.1-1ubuntu1.9

Ubuntu 16.04 ESM:
exim4-base 4.86.2-2ubuntu2.6+esm2
exim4-daemon-heavy 4.86.2-2ubuntu2.6+esm2
exim4-daemon-light 4.86.2-2ubuntu2.6+esm2

Ubuntu 14.04 ESM:
exim4-base 4.82-3ubuntu2.4+esm4
exim4-daemon-heavy 4.82-3ubuntu2.4+esm4
exim4-daemon-light 4.82-3ubuntu2.4+esm4

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

References:
  https://ubuntu.com/security/notices/USN-5574-1
CVE-2022-37452

Package Information:
  https://launchpad.net/ubuntu/+source/exim4/4.93-13ubuntu1.6
  https://launchpad.net/ubuntu/+source/exim4/4.90.1-1ubuntu1.9