USN-7954-1: Libtasn1 vulnerabilities

USN-7954-1: Libtasn1 vulnerabilities
Publication date: 12 January 2026
Overview: Libtasn1 could be made to crash if it received specially crafted input.

Packages
libtasn1-6 - Library to manage ASN.1 structures

Details
It was discovered that Libtasn1 incorrectly handled decoding ASN.1 content.
An attacker could possibly use this issue to cause Libtasn1 to crash,
resulting in a denial of service. (CVE-2025-13151)

It was discovered that Libtasn1 incorrectly handled encoding ASN.1 content.
An attacker could possibly use this issue to cause Libtasn1 to crash,
resulting in a denial of service. This issue only affected Ubuntu 22.04
LTS. (CVE-2021-46848)

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

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

25.10 questing
libtasn1-6 – 4.20.0-2ubuntu0.25.10.1

25.04 plucky
libtasn1-6 – 4.20.0-2ubuntu0.25.04.1

24.04 LTS

• noble libtasn1-6 – 4.19.0-3ubuntu0.24.04.2

22.04 LTS jammy

• libtasn1-6 – 4.18.0-4ubuntu0.2