1. Ubuntu Security Notices
  2. USN-3138-1

USN-3138-1: python-cryptography vulnerability

Publication date

28 November 2016

Overview

python-cryptography could generate incorrect keys.

Releases

Packages

Details

Markus Döring discovered that python-cryptography incorrectly handled
certain HKDF lengths. This could result in python-cryptography returning an
empty string instead of the expected derived key.

Markus Döring discovered that python-cryptography incorrectly handled
certain HKDF lengths. This could result in python-cryptography returning an
empty string instead of the expected derived key.

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
16.10 yakkety python-cryptography –  1.5-2ubuntu0.1
python3-cryptography –  1.5-2ubuntu0.1
16.04 LTS xenial python-cryptography –  1.2.3-1ubuntu0.1
python3-cryptography –  1.2.3-1ubuntu0.1

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References

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