High (7.8). EPSS 1.4% chance of exploitation in the next 30 days.
A flaw was found in X.Org server. In the XISendDeviceHierarchyEvent function, it is possible to exceed the allocated array length when certain new device IDs are added to the xXIHierarchyInfo struct. This can trigger a heap buffer overflow condition, which may lead to an application crash or remote code execution in SSH X11 forwarding environments.
Severity
CVSS 3.1
7.8 high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
1.4% chance of exploitation in the next 30 days; higher than 72% of CVEs (scores of 2026-10-31)