=========================================================================Ubuntu Security Notice USN-4700-1
January 19, 2021

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

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 ESM

Summary:

PyXDG could be made to run programs as your login if it received specially
crafted input.

Software Description:
- pyxdg: python library to access freedesktop.org standards

Details:

Alexandre D'Hondt discovered that PyXDG did not properly sanitize input.
An attacker could exploit this with a crafted .menu file to execute
arbitrary code.

Update instructions:

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

Ubuntu 18.04 LTS:
  python-xdg                      0.25-4ubuntu1.1
  python3-xdg                     0.25-4ubuntu1.1

Ubuntu 16.04 LTS:
  python-xdg                      0.25-4ubuntu0.16.04.1
  python3-xdg                     0.25-4ubuntu0.16.04.1

Ubuntu 14.04 ESM:
  python-xdg                      0.25-4ubuntu0.14.04.1~esm1
  python3-xdg                     0.25-4ubuntu0.14.04.1~esm1

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

References:
  https://ubuntu.com/security/notices/USN-4700-1
  CVE-2019-12761

Package Information:
  https://launchpad.net/ubuntu/+source/pyxdg/0.25-4ubuntu1.1
  https://launchpad.net/ubuntu/+source/pyxdg/0.25-4ubuntu0.16.04.1