An Apache HTTP Server security update has been released for Ubuntu Linux 20.04 LTS, 22.04 LTS, 23.04, and 23.10.

[USN-6506-1] Apache HTTP Server vulnerabilities

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Ubuntu Security Notice USN-6506-1
November 22, 2023

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

- Ubuntu 23.10
- Ubuntu 23.04
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS

Summary:

Several security issues were fixed in Apache HTTP Server.

Software Description:
- apache2: Apache HTTP server

Details:

David Shoon discovered that the Apache HTTP Server mod_macro module
incorrectly handled certain memory operations. A remote attacker could
possibly use this issue to cause the server to crash, resulting in a denial
of service. (CVE-2023-31122)

Prof. Sven Dietrich, Isa Jafarov, Prof. Heejo Lee, and Choongin Lee
discovered that the Apache HTTP Server incorrectly handled certain HTTP/2
connections. A remote attacker could possibly use this issue to cause the
server to consume resources, leading to a denial of service. This issue
only affected Ubuntu 23.04, and Ubuntu 23.10. (CVE-2023-43622)

Will Dormann and David Warren discovered that the Apache HTTP Server
incorrectly handled memory when handling HTTP/2 connections. A remote
attacker could possibly use this issue to cause the server to consume
resources, leading to a denial of service. (CVE-2023-45802)

Update instructions:

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

Ubuntu 23.10:
apache2 2.4.57-2ubuntu2.1

Ubuntu 23.04:
apache2 2.4.55-1ubuntu2.1

Ubuntu 22.04 LTS:
apache2 2.4.52-1ubuntu4.7

Ubuntu 20.04 LTS:
apache2 2.4.41-4ubuntu3.15

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

References:
https://ubuntu.com/security/notices/USN-6506-1
CVE-2023-31122, CVE-2023-43622, CVE-2023-45802

Package Information:
https://launchpad.net/ubuntu/+source/apache2/2.4.57-2ubuntu2.1
https://launchpad.net/ubuntu/+source/apache2/2.4.55-1ubuntu2.1
https://launchpad.net/ubuntu/+source/apache2/2.4.52-1ubuntu4.7
https://launchpad.net/ubuntu/+source/apache2/2.4.41-4ubuntu3.15