USN-6611-1: Exim vulnerability

Releases

• Ubuntu 23.10
• Ubuntu 22.04 LTS
• Ubuntu 20.04 LTS
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM

Packages

• exim4 - Exim is a mail transport agent

Details

It was discovered that Exim incorrectly handled certain requests.
A remote attacker could possibly use a published exploitation technique
to inject e-mail messages with a spoofed MAIL FROM address, allowing bypass
of an SPF protection mechanism.

Update instructions

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

Ubuntu 23.10

• exim4 - 4.96-17ubuntu2.2
• exim4-base - 4.96-17ubuntu2.2
• eximon4 - 4.96-17ubuntu2.2

Ubuntu 22.04

• exim4 - 4.95-4ubuntu2.5
• exim4-base - 4.95-4ubuntu2.5
• eximon4 - 4.95-4ubuntu2.5

Ubuntu 20.04

• exim4 - 4.93-13ubuntu1.10
• exim4-base - 4.93-13ubuntu1.10
• eximon4 - 4.93-13ubuntu1.10

Ubuntu 18.04

• exim4 - 4.90.1-1ubuntu1.10+esm3
  Available with Ubuntu Pro
• exim4-base - 4.90.1-1ubuntu1.10+esm3
  Available with Ubuntu Pro
• eximon4 - 4.90.1-1ubuntu1.10+esm3
  Available with Ubuntu Pro

Ubuntu 16.04

• exim4 - 4.86.2-2ubuntu2.6+esm6
  Available with Ubuntu Pro
• exim4-base - 4.86.2-2ubuntu2.6+esm6
  Available with Ubuntu Pro
• eximon4 - 4.86.2-2ubuntu2.6+esm6
  Available with Ubuntu Pro

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

References

• CVE-2023-51766