USN-7742-1: GnuTLS vulnerabilities

Publication date

9 September 2025

Overview

Several security issues were fixed in GnuTLS.


Packages

Details

It was discovered that GnuTLS incorrectly handled exporting Subject
Alternative Name (SAN) entries containing an otherName. A remote attacker
could use this issue to cause GnuTLS to crash, resulting in a denial of
service, or possibly execute arbitrary code. This issue only affected
Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2025-32988)

It was discovered that the GnuTLS certtool utility incorrectly handled
parsing certain template files. An attacker could use this issue to cause
GnuTLS to crash, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2025-32990)

Stefan Bühler discovered that GnuTLS incorrectly handled parsing certain
template files. An attacker could possibly use this issue to cause GnuTLS
to crash, resulting in a denial of service. This issue only affected
Ubuntu 20.04 LTS. (

It was discovered that GnuTLS incorrectly handled exporting Subject
Alternative Name (SAN) entries containing an otherName. A remote attacker
could use this issue to cause GnuTLS to crash, resulting in a denial of
service, or possibly execute arbitrary code. This issue only affected
Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2025-32988)

It was discovered that the GnuTLS certtool utility incorrectly handled
parsing certain template files. An attacker could use this issue to cause
GnuTLS to crash, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2025-32990)

Stefan Bühler discovered that GnuTLS incorrectly handled parsing certain
template files. An attacker could possibly use this issue to cause GnuTLS
to crash, resulting in a denial of service. This issue only affected
Ubuntu 20.04 LTS. (CVE-2025-6395)


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
20.04 focal libgnutls30 –  3.6.13-2ubuntu1.12+esm1  
18.04 bionic libgnutls30 –  3.5.18-1ubuntu1.6+esm2  
16.04 xenial libgnutls30 –  3.4.10-4ubuntu1.9+esm2  

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