An Apache HTTP Server security update has been released for Ubuntu 16.04 ESM.

USN-5942-2: Apache HTTP Server vulnerability

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Ubuntu Security Notice USN-5942-2
March 22, 2023

apache2 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 ESM

Summary:

Apache HTTP Server could allow unintended access to network services.

Software Description:
- apache2: Apache HTTP server

Details:

USN-5942-1 fixed vulnerabilities in Apache HTTP Server. This update
provides the corresponding update for CVE-2023-25690 for Ubuntu 16.04 ESM.

Original advisory details:

Lars Krapf discovered that the Apache HTTP Server mod_proxy module
incorrectly handled certain configurations. A remote attacker could
possibly use this issue to perform an HTTP Request Smuggling attack.
(CVE-2023-25690)

Update instructions:

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

Ubuntu 16.04 ESM:
apache2 2.4.18-2ubuntu3.17+esm10

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

References:
https://ubuntu.com/security/notices/USN-5942-2
https://ubuntu.com/security/notices/USN-5942-1
CVE-2023-25690