USN-3520-1: PySAML2 vulnerability

Ubuntu Security Notice USN-3520-1

8th January, 2018

python-pysaml2 vulnerability

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 17.10
  • Ubuntu 17.04
  • Ubuntu 16.04 LTS


PySAML2 could allow authentication without a password.

Software description

  • python-pysaml2 - Pure python implementation of SAML2


It was discovered that PySAML2 incorrectly accepted any password when run
with python optimizations enabled. An attacker could use this issue to
authenticate as any user without a valid password.

Update instructions

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

Ubuntu 17.10:
python-pysaml2 3.0.0-3ubuntu2.2
python3-pysaml2 3.0.0-3ubuntu2.2
Ubuntu 17.04:
python-pysaml2 3.0.0-3ubuntu1.17.04.3
python3-pysaml2 3.0.0-3ubuntu1.17.04.3
Ubuntu 16.04 LTS:
python-pysaml2 3.0.0-3ubuntu1.16.04.3
python3-pysaml2 3.0.0-3ubuntu1.16.04.3

To update your system, please follow these instructions:

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