CVE-2026-88806: X.org LIBX11

High severity, CVSS 7.5. EPSS: 0.2% chance of exploitation in the next 30 days.

A malicious X server could exploit a buffer overflow in libX11 before 1.8.14 during handling of XkbGetMap overflowing the key_sym_map.

Affected products

• X.org LIBX11: before 1.8.14 (fixed in 1.8.14)

Published 2026-09-21. Last modified 2026-09-22.