USN-2098-2: LibYAML regression

13 February 2014

libyaml regression

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

  • Ubuntu 13.10
  • Ubuntu 12.10
  • Ubuntu 12.04 LTS


USN-2098-1 introduced a regression in LibYAML.

Software Description

  • libyaml - Fast YAML 1.1 parser and emitter library


USN-2098-1 fixed a vulnerability in LibYAML. The security fix used introduced a regression that caused parsing failures for certain valid YAML files. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Florian Weimer discovered that LibYAML incorrectly handled certain large yaml documents. An attacker could use this issue to cause LibYAML to crash, resulting in a denial of service, or possibly execute arbitrary code.

Update instructions

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

Ubuntu 13.10
libyaml-0-2 - 0.1.4-2ubuntu0.13.10.2
Ubuntu 12.10
libyaml-0-2 - 0.1.4-2ubuntu0.12.10.2
Ubuntu 12.04 LTS
libyaml-0-2 - 0.1.4-2ubuntu0.12.04.2

To update your system, please follow these instructions:

After a standard system update you need to restart applications using LibYAML to make all the necessary changes.