USN-7954-1: Libtasn1 vulnerabilities

Publication date

12 January 2026

Overview

Libtasn1 could be made to crash if it received specially crafted input.


Packages

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)

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.

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 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

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