CVE-2018-15853: Canonical Ubuntu Linux

Medium severity, CVSS 5.5. EPSS: 0.5% chance of exploitation in the next 30 days.

Endless recursion exists in xkbcomp/expr.c in xkbcommon and libxkbcommon before 0.8.1, which could be used by local attackers to crash xkbcommon users by supplying a crafted keymap file that triggers boolean negation.

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.