USN-8087-1: python-cryptography vulnerability

Publication date

12 March 2026

Overview

python-cryptography could be made to expose sensitive information over the network.


Packages

Details

It was discovered that python-cryptography incorrectly handled subgroup
validation for SECT curves. A remote attacker could use this issue to
perform a subgroup attack and possibly recover the least significant bits
of private keys.

It was discovered that python-cryptography incorrectly handled subgroup
validation for SECT curves. A remote attacker could use this issue to
perform a subgroup attack and possibly recover the least significant bits
of private keys.

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-cryptography –  43.0.0-1ubuntu1.1
24.04 LTS noble python3-cryptography –  41.0.7-4ubuntu0.3
22.04 LTS jammy python3-cryptography –  3.4.8-1ubuntu2.3

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