APT could be made to overwrite files.
Guillem Jover discovered that APT incorrectly created a temporary file when handling the changelog command. A local attacker could use this issue to overwrite arbitrary files. In the default installation of Ubuntu, this should be prevented by the kernel link restrictions.
8 October 2014
A security issue affects these releases of Ubuntu and its derivatives:
APT could be made to overwrite files.
Guillem Jover discovered that APT incorrectly created a temporary file when handling the changelog command. A local attacker could use this issue to overwrite arbitrary files. In the default installation of Ubuntu, this should be prevented by the kernel link restrictions.
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.