USN-8524-1: Python vulnerability

Publication date

9 July 2026

Overview

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

Releases


Packages

  • python2.7 - An interactive high-level object-oriented language
  • python3.5 - An interactive high-level object-oriented language

Details

It was discovered that Python did not use sufficient entropy for Expat
hash-flooding protection in the xml.parsers.expat and xml.etree.ElementTree
modules. An attacker could use this to cause a denial of service via a
crafted XML document.

It was discovered that Python did not use sufficient entropy for Expat
hash-flooding protection in the xml.parsers.expat and xml.etree.ElementTree
modules. An attacker could use this to cause a denial of service via a
crafted XML document.

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
16.04 LTS xenial idle-python2.7 –  2.7.12-1ubuntu0~16.04.18+esm20  
idle-python3.5 –  3.5.2-2ubuntu0~16.04.13+esm23  
libpython2.7 –  2.7.12-1ubuntu0~16.04.18+esm20  
libpython2.7-dev –  2.7.12-1ubuntu0~16.04.18+esm20  
libpython2.7-minimal –  2.7.12-1ubuntu0~16.04.18+esm20  
libpython2.7-stdlib –  2.7.12-1ubuntu0~16.04.18+esm20  
libpython2.7-testsuite –  2.7.12-1ubuntu0~16.04.18+esm20  
libpython3.5 –  3.5.2-2ubuntu0~16.04.13+esm23  
libpython3.5-dev –  3.5.2-2ubuntu0~16.04.13+esm23  
libpython3.5-minimal –  3.5.2-2ubuntu0~16.04.13+esm23  
libpython3.5-stdlib –  3.5.2-2ubuntu0~16.04.13+esm23  
libpython3.5-testsuite –  3.5.2-2ubuntu0~16.04.13+esm23  
python2.7 –  2.7.12-1ubuntu0~16.04.18+esm20  
python2.7-dev –  2.7.12-1ubuntu0~16.04.18+esm20  
python2.7-doc –  2.7.12-1ubuntu0~16.04.18+esm20  
python2.7-examples –  2.7.12-1ubuntu0~16.04.18+esm20  
python2.7-minimal –  2.7.12-1ubuntu0~16.04.18+esm20  
python3.5 –  3.5.2-2ubuntu0~16.04.13+esm23  
python3.5-dev –  3.5.2-2ubuntu0~16.04.13+esm23  
python3.5-doc –  3.5.2-2ubuntu0~16.04.13+esm23  
python3.5-examples –  3.5.2-2ubuntu0~16.04.13+esm23  
python3.5-minimal –  3.5.2-2ubuntu0~16.04.13+esm23  
python3.5-venv –  3.5.2-2ubuntu0~16.04.13+esm23  

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.


Have additional questions?

Talk to a member of the team ›