Ubuntu alert USN-6409-1 (glibc)

From:
             
 
Marc Deslauriers <marc.deslauriers@canonical.com>
To:
             
 
"ubuntu-security-announce@lists.ubuntu.com" <ubuntu-security-announce@lists.ubuntu.com>
Subject:
             
 
[USN-6409-1] GNU C Library vulnerabilities
Date:
             
 
Tue, 03 Oct 2023 15:41:07 -0400
Message-ID:
             
 
<d25d5d50-f902-d785-f1a0-91cddd8b09d5@canonical.com>
==========================================================================
Ubuntu Security Notice USN-6409-1
October 03, 2023

glibc vulnerabilities
==========================================================================

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

- Ubuntu 23.04
- Ubuntu 22.04 LTS

Summary:

Several security issues were fixed in GNU C Library.

Software Description:
- glibc: GNU C Library

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)

Update instructions:

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

Ubuntu 23.04:
   libc6                           2.37-0ubuntu2.1

Ubuntu 22.04 LTS:
   libc6                           2.35-0ubuntu3.4

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

References:
   https://ubuntu.com/security/notices/USN-6409-1
   CVE-2023-4527, CVE-2023-4911

Package Information:
   https://launchpad.net/ubuntu/+source/glibc/2.37-0ubuntu2.1
   https://launchpad.net/ubuntu/+source/glibc/2.35-0ubuntu3.4