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

USN-5583-1: systemd vulnerability

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Ubuntu Security Notice USN-5583-1
August 29, 2022

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

- Ubuntu 18.04 LTS

Summary:

systemd could be made to crash or run programs if it received specially
crafted DNS request.

Software Description:
- systemd: system and service manager

Details:

It was discovered that systemd incorrectly handled certain DNS requests,
which leads to user-after-free vulnerability. An attacker could possibly use
this issue to cause a crash or execute arbitrary code. (CVE-2022-2526)

Update instructions:

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

Ubuntu 18.04 LTS:
systemd 237-3ubuntu10.54

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

References:
  https://ubuntu.com/security/notices/USN-5583-1
CVE-2022-2526

Package Information:
  https://launchpad.net/ubuntu/+source/systemd/237-3ubuntu10.54