CVE-2018-6556: Canonical Ubuntu Linux

Low severity, CVSS 3.3. EPSS: 0.3% chance of exploitation in the next 30 days.

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.

Affected products

• Canonical Ubuntu Linux: version 18.04 only
• Linuxcontainers Lxc: from 2.0.0, up to and including 2.0.9; from 3.0.0, before 3.0.2 (fixed in 3.0.2)
• Opensuse Leap: version 15.0 only
• Suse Caas Platform: version 1.0 only; version 2.0 only
• Suse Openstack Cloud: version 6 only
• Suse Suse Linux Enterprise Server: version 11 only

Published 2018-08-10. Last modified 2026-06-17.