USN-6409-1: GNU C Library vulnerabilities

3 October 2023

Several security issues were fixed in GNU C Library.

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Releases

Packages

Details

It was discovered that the GNU C Library incorrectly handled the
GLIBC_TUNABLES environment variable. An attacker could possibly use this
issue to perform a privilege escalation attack. (CVE-2023-4911)

It was discovered that the GNU C Library incorrectly handled certain DNS
responses when the system was configured in no-aaaa mode. A remote attacker
could possibly use this issue to cause the GNU C Library to crash,
resulting in a denial of service. This issue only affected Ubuntu 23.04.
(CVE-2023-4527)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 23.04
Ubuntu 22.04

After a standard system update you need to reboot your computer to make all
the necessary changes.