USN-8043-1: GnuTLS vulnerabilities

Publication date

16 February 2026

Overview

Several security issues were fixed in GnuTLS.


Packages

Details

Tim Scheckenbach discovered that GnuTLS incorrectly handled malicious
certificates containing a large number of name constraints and subject
alternative names. A remote attacker could possibly use this issue to
cause GnuTLS to consume resources, resulting in a denial of service.
(CVE-2025-14831)

Luigino Camastra discovered that GnuTLS incorrectly handled certain PKCS11
token labels. A remote attacker could use this issue to cause GnuTLS to
crash, resulting in a denial of service, or possibly execute arbitrary
code. The default compiler options for affected releases should reduce the
vulnerability to a denial of service. (CVE-2025-9820)

Tim Scheckenbach discovered that GnuTLS incorrectly handled malicious
certificates containing a large number of name constraints and subject
alternative names. A remote attacker could possibly use this issue to
cause GnuTLS to consume resources, resulting in a denial of service.
(CVE-2025-14831)

Luigino Camastra discovered that GnuTLS incorrectly handled certain PKCS11
token labels. A remote attacker could use this issue to cause GnuTLS to
crash, resulting in a denial of service, or possibly execute arbitrary
code. The default compiler options for affected releases should reduce the
vulnerability to a denial of service. (CVE-2025-9820)

Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
25.10 questing libgnutls30t64 –  3.8.9-3ubuntu2.1
24.04 LTS noble libgnutls30t64 –  3.8.3-1.1ubuntu3.5
22.04 LTS jammy libgnutls30 –  3.7.3-4ubuntu1.8

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