USN-2104-1: LXC vulnerability

12 February 2014

lxc vulnerability

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

  • Ubuntu 13.10

Summary

LXC would allow unintended access to the host, bypassing intended confinement.

Software Description

  • lxc - Linux Containers userspace tools

Details

Florian Sagar discovered that the LXC sshd template set incorrect mount permissions. An attacker could possibly use this flaw to cause privilege escalation on the host.

Update instructions

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

Ubuntu 13.10
lxc-templates - 1.0.0~alpha1-0ubuntu14.1

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

After a standard system update you need to recreate LXC containers created with the sshd template to make all the necessary changes.

References