USN-6411-1: Exim vulnerabilities

4 October 2023

Several security issues were fixed in Exim.

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Releases

Packages

  • exim4 - Exim is a mail transport agent

Details

It was discovered that Exim incorrectly handled certain challenge requests.
A remote attacker could possibly use this issue to perform out-of-bounds
reads, resulting in information leakage. (CVE-2023-42114)

It was discovered that Exim incorrectly handled validation of user-supplied
data. A remote attacker could possibly use this issue to perform
out-of-bounds writes, resulting in arbitrary code execution. This issue
only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS and Ubuntu 23.04.
(CVE-2023-42115)

It was discovered that Exim incorrectly handled certain challenge requests.
A remote attacker could possibly use this issue to perform out-of-bounds
writes, resulting in arbitrary code execution. (CVE-2023-42116)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 23.04
Ubuntu 22.04
Ubuntu 20.04
Ubuntu 18.04
Ubuntu 16.04
Ubuntu 14.04

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