USN-2675-1: LXC vulnerabilities

22 July 2015

lxc vulnerabilities

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

  • Ubuntu 15.04
  • Ubuntu 14.10
  • Ubuntu 14.04 LTS

Summary

Several security issues were fixed in LXC.

Software Description

  • lxc - Linux Containers userspace tools

Details

Roman Fiedler discovered that LXC had a directory traversal flaw when creating lock files. A local attacker could exploit this flaw to create an arbitrary file as the root user. (CVE-2015-1331)

Roman Fiedler discovered that LXC incorrectly trusted the container’s proc filesystem to set up AppArmor profile changes and SELinux domain transitions. A local attacker could exploit this flaw to run programs inside the container that are not confined by AppArmor or SELinux. (CVE-2015-1334)

Update instructions

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

Ubuntu 15.04
liblxc1 - 1.1.2-0ubuntu3.1
lxc - 1.1.2-0ubuntu3.1
Ubuntu 14.10
liblxc1 - 1.1.0~alpha2-0ubuntu3.3
lxc - 1.1.0~alpha2-0ubuntu3.3
Ubuntu 14.04 LTS
liblxc1 - 1.0.7-0ubuntu0.2
lxc - 1.0.7-0ubuntu0.2

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. You will need to restart your previously running LXC containers in Ubuntu 15.04 due to bug that causes containers to be stopped on during lxc package installation (https://launchpad.net/bugs/1476691).

References