Ubuntu 25.10: Libtasn1 Important DoS Crash Flaw USN-7954-1

ubuntu

January 12, 2026

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

Summary

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

Software Description:

- 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)

Topics Covered

security advisory DoS Ubuntu important crash libtasn1

Update Instructions

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

Ubuntu 25.10
  libtasn1-6                      4.20.0-2ubuntu0.25.10.1

Ubuntu 25.04
  libtasn1-6                      4.20.0-2ubuntu0.25.04.1

Ubuntu 24.04 LTS
  libtasn1-6                      4.19.0-3ubuntu0.24.04.2

Ubuntu 22.04 LTS
  libtasn1-6                      4.18.0-4ubuntu0.2

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