USN-1477-1: APT vulnerability

15 June 2012

apt vulnerability

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

  • Ubuntu 12.04 LTS
  • Ubuntu 11.10
  • Ubuntu 11.04
  • Ubuntu 10.04 LTS
  • Ubuntu 8.04 LTS


An attacker could trick APT into installing altered packages.

Software Description

  • apt - Advanced front-end for dpkg


Georgi Guninski discovered that APT did not properly validate imported keyrings via apt-key net-update. USN-1475-1 added additional verification for imported keyrings, but it was insufficient. If a remote attacker were able to perform a man-in-the-middle attack, this flaw could potentially be used to install altered packages. This update corrects the issue by disabling the net-update option completely. A future update will re-enable the option with corrected verification.

Update instructions

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

Ubuntu 12.04 LTS
apt - 0.8.16~exp12ubuntu10.2
Ubuntu 11.10
apt - 0.8.16~exp5ubuntu13.5
Ubuntu 11.04
apt -
Ubuntu 10.04 LTS
apt -
Ubuntu 8.04 LTS
apt - 0.7.9ubuntu17.6

To update your system, please follow these instructions:

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