An attacker could trick APT into installing altered source packages.
Jakub Wilk discovered that APT did not correctly validate signatures when downloading source packages. If a remote attacker were able to perform a man-in-the-middle attack, this flaw could potentially be used to install altered source packages.
17 June 2014
A security issue affects these releases of Ubuntu and its derivatives:
An attacker could trick APT into installing altered source packages.
Jakub Wilk discovered that APT did not correctly validate signatures when downloading source packages. If a remote attacker were able to perform a man-in-the-middle attack, this flaw could potentially be used to install altered source packages.
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.
Vulmon