CVE-2018-6556

lxc-user-nic when asked to delete a network interface will unconditionally
open a user provided path. This code path may be used by an unprivileged
user to check for the existence of a path which they wouldn’t otherwise be
able to reach. It may also be used to trigger side effects by causing a
(read-only) open of special kernel files (ptmx, proc, sys). Affected
releases are LXC: 2.0 versions above and including 2.0.9; 3.0 versions
above and including 3.0.0, prior to 3.0.2.

Bugs

• <https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1783591&gt;