CVE-2018-15858: Canonical Ubuntu Linux

Medium severity, CVSS 5.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Unchecked NULL pointer usage when handling invalid aliases in CopyKeyAliasesToKeymap in xkbcomp/keycodes.c in xkbcommon before 0.8.1 could be used by local attackers to crash (NULL pointer dereference) the xkbcommon parser by supplying a crafted keymap file.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 18.04 only
• Xkbcommon Libxkbcommon: before 0.8.1 (fixed in 0.8.1)
• Xkbcommon Xkbcommon: before 0.8.1 (fixed in 0.8.1)

Published 2018-08-25. Last modified 2026-06-17.