Ubuntu 4245-1 Critical: Addressing PySAML2 Signature Bypass Vulnerability

ubuntu

January 21, 2020

PySAML2 could be made to bypass signature verification with arbitrary data.

Summary

PySAML2 could be made to bypass signature verification with arbitrary data.

Software Description:

- python-pysaml2: Pure python implementation of SAML2

Details:

It was discovered that PySAML2 incorrectly handled certain SAML files.

An attacker could possibly use this issue to bypass signature verification

with arbitrary data.

Topics Covered

security advisory critical software update Ubuntu signature bypass PySAML2 arbitrary data

Update Instructions

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

Ubuntu 19.10:
  python-pysaml2                  4.5.0+dfsg1-0ubuntu2.19.10.1
  python3-pysaml2                 4.5.0+dfsg1-0ubuntu2.19.10.1

Ubuntu 19.04:
  python-pysaml2                  4.5.0+dfsg1-0ubuntu2.19.04.1
  python3-pysaml2                 4.5.0+dfsg1-0ubuntu2.19.04.1

Ubuntu 18.04 LTS:
  python-pysaml2                  4.0.2-0ubuntu3.1
  python3-pysaml2                 4.0.2-0ubuntu3.1

Ubuntu 16.04 LTS:
  python-pysaml2                  3.0.0-3ubuntu1.16.04.4
  python3-pysaml2                 3.0.0-3ubuntu1.16.04.4

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