USN-2753-3: LXC regression

5 October 2015

lxc regression

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

  • Ubuntu 14.04 LTS

Summary

USN-2753-1 introduced a regression in LXC.

Software Description

  • lxc - Linux Containers userspace tools

Details

USN-2753-1 fixed a vulnerability in LXC. The update caused a regression that prevented some containers from starting. This regression only affected containers that had a path that contained a ‘/./’ directory specified as a bind mount target in their configuration file. This update fixes the problem. We apologize for the inconvenience.

Original advisory details:

Roman Fiedler discovered a directory traversal flaw in lxc-start. A local attacker with access to an LXC container could exploit this flaw to run programs inside the container that are not confined by AppArmor or expose unintended files in the host to the container.

Update instructions

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

Ubuntu 14.04 LTS
liblxc1 - 1.0.7-0ubuntu0.7
lxc - 1.0.7-0ubuntu0.7
lxc-dev - 1.0.7-0ubuntu0.7
lxc-templates - 1.0.7-0ubuntu0.7
lxc-tests - 1.0.7-0ubuntu0.7
python3-lxc - 1.0.7-0ubuntu0.7

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.

References