USN-7975-1: pyasn1 vulnerability

Publication date

22 January 2026

Overview

pyasn1 could be made to crash if it received specially crafted input.


Packages

  • pyasn1 - ASN.1 library for Python

Details

It was discovered that pyasn1 incorrectly handled malformed RELATIVE-OIDs
with excessive continuation octets. An attacker could possibly use this
issue to cause pyasn1 to consume memory, leading to a denial of service.

It was discovered that pyasn1 incorrectly handled malformed RELATIVE-OIDs
with excessive continuation octets. An attacker could possibly use this
issue to cause pyasn1 to consume memory, leading to a denial of service.

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 python3-pyasn1 –  0.6.1-1ubuntu0.1
24.04 LTS noble python3-pyasn1 –  0.4.8-4ubuntu0.1
22.04 LTS jammy python3-pyasn1 –  0.4.8-1ubuntu0.1

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