==========================================================================
Ubuntu Security Notice USN-6541-2
January 10, 2024

glibc regression
==========================================================================

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

- Ubuntu 22.04 LTS

Summary:

USN-6541-1 introduced a regression in the GNU C Library.

Software Description:
- glibc: GNU C Library

Details:

USN-6541-1 fixed vulnerabilities in the GNU C Library. Unfortunately,
changes made to allow proper application of the fix for CVE-2023-4806 in
Ubuntu 22.04 LTS introduced an issue in the NSCD service IPv6 processing
functionalities. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

It was discovered that the GNU C Library was not properly handling certain
memory operations. An attacker could possibly use this issue to cause a
denial of service (application crash). (CVE-2023-4806, CVE-2023-4813)

It was discovered that the GNU C library was not properly implementing a
fix for CVE-2023-4806 in certain cases, which could lead to a memory leak.
An attacker could possibly use this issue to cause a denial of service
(application crash). This issue only affected Ubuntu 22.04 LTS and Ubuntu
23.04. (CVE-2023-5156)

Update instructions:

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

Ubuntu 22.04 LTS:
libc-bin 2.35-0ubuntu3.6
libc6 2.35-0ubuntu3.6
nscd 2.35-0ubuntu3.6

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

References:
https://ubuntu.com/security/notices/USN-6541-2
https://ubuntu.com/security/notices/USN-6541-1
https://launchpad.net/bugs/2047155

Package Information:
https://launchpad.net/ubuntu/+source/glibc/2.35-0ubuntu3.6