A CUPS security update has been released for Ubuntu Linux 16.04 LTS and 18.04 LTS.

[USN-6391-2] CUPS vulnerability

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Ubuntu Security Notice USN-6391-2
September 21, 2023

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

- Ubuntu 18.04 LTS (Available with Ubuntu Pro)
- Ubuntu 16.04 LTS (Available with Ubuntu Pro)

Summary:

CUPS could be made to crash or run programs if it opened a specially
crafted file.

Software Description:
- cups: Common UNIX Printing System(tm)

Details:

USN-6391-1 fixed a vulnerability in CUPS. This update provides
the corresponding update for Ubuntu 16.04 LTS and Ubuntu 18.04 LTS.

Original advisory details:

It was discovered that CUPS incorrectly parsed certain Postscript objects.
If a user or automated system were tricked into printing a specially
crafted document, a remote attacker could use this issue to cause CUPS to
crash, resulting in a denial of service, or possibly execute arbitrary
code.

Update instructions:

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

Ubuntu 18.04 LTS (Available with Ubuntu Pro):
cups 2.2.7-1ubuntu2.10+esm2

Ubuntu 16.04 LTS (Available with Ubuntu Pro):
cups 2.1.3-4ubuntu0.11+esm4

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

References:
https://ubuntu.com/security/notices/USN-6391-2
https://ubuntu.com/security/notices/USN-6391-1
CVE-2023-4504