=========================================================================Ubuntu Security Notice USN-1283-1
November 28, 2011

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

- Ubuntu 11.04
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 8.04 LTS

Summary:

APT could be made to expose sensitive information over the network.

Software Description:
- apt: Advanced front-end for dpkg

Details:

It was discovered that APT incorrectly handled the Verify-Host
configuration option. If a remote attacker were able to perform a
man-in-the-middle attack, this flaw could potentially be used to steal
repository credentials. This issue only affected Ubuntu 10.04 LTS and
10.10. (CVE-2011-3634)

USN-1215-1 fixed a vulnerability in APT by disabling the apt-key net-update
option. This update re-enables the option with corrected verification.
Original advisory details:
 It was discovered that the apt-key utility incorrectly verified GPG
 keys when downloaded via the net-update option. If a remote attacker were
 able to perform a man-in-the-middle attack, this flaw could potentially be
 used to install altered packages.

Update instructions:

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

Ubuntu 11.04:
  apt                             0.8.13.2ubuntu4.3

Ubuntu 10.10:
  apt                             0.8.3ubuntu7.3

Ubuntu 10.04 LTS:
  apt                             0.7.25.3ubuntu9.9

Ubuntu 8.04 LTS:
  apt                             0.7.9ubuntu17.4

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

References:
  https://ubuntu.com/security/notices/USN-1283-1
  CVE-2011-3634

Package Information:
  https://launchpad.net/ubuntu/+source/apt/0.8.13.2ubuntu4.3
  https://launchpad.net/ubuntu/+source/apt/0.8.3ubuntu7.3
  https://launchpad.net/ubuntu/+source/apt/0.7.25.3ubuntu9.9
  https://launchpad.net/ubuntu/+source/apt/0.7.9ubuntu17.4