USN-3356-1: Expat vulnerability

19 July 2017

expat vulnerability

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

  • Ubuntu 17.04
  • Ubuntu 16.10
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 LTS


Expat could be made to hang if it received specially crafted input.

Software Description

  • expat - XML parsing C library


It was discovered that Expat incorrectly handled certain external entities. A remote attacker could possibly use this issue to cause Expat to hang, resulting in a denial of service.

Update instructions

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

Ubuntu 17.04
lib64expat1 - 2.2.0-2ubuntu0.1
libexpat1 - 2.2.0-2ubuntu0.1
Ubuntu 16.10
lib64expat1 - 2.2.0-1ubuntu0.1
libexpat1 - 2.2.0-1ubuntu0.1
Ubuntu 16.04 LTS
lib64expat1 - 2.1.0-7ubuntu0.16.04.3
libexpat1 - 2.1.0-7ubuntu0.16.04.3
Ubuntu 14.04 LTS
lib64expat1 - 2.1.0-4ubuntu1.4
libexpat1 - 2.1.0-4ubuntu1.4

To update your system, please follow these instructions:

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