A GnuPG security update has been released for Ubuntu Linux 18.04 LTS.

==========================================================================
Ubuntu Security Notice USN-5431-1
May 30, 2022

gnupg2 vulnerability
==========================================================================

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

- Ubuntu 18.04 LTS

Summary:

GnuPG could be made to stop responding.

Software Description:
- gnupg2: GNU privacy guard - a free PGP replacement

Details:

It was discovered that GnuPG was not properly processing keys
with large amounts of signatures. An attacker could possibly
use this issue to cause a denial of service.

Update instructions:

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

Ubuntu 18.04 LTS:
gnupg 2.2.4-1ubuntu1.5

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

References:
https://ubuntu.com/security/notices/USN-5431-1
CVE-2019-13050

Package Information:
https://launchpad.net/ubuntu/+source/gnupg2/2.2.4-1ubuntu1.5