What is CVE-2026-93518?

CVE-2026-93518 is a high-severity vulnerability in X.org Xorg-X11-Server, classified under Heap-based Buffer Overflow. CVSS score: 7.8/10. Published 2026-10-28.

How severe is CVE-2026-93518?

High severity. CVSS v3 base score is 7.8 out of 10.

Buffer overflow in X.org Xorg-X11-Server

CVE-2026-93518

An integer truncation issue in XkbResizeKeyType() that could lead to a heap buffer overflow by authenticated X clients in X.org X server before 21.1.25 and XWayland before 24.1.14 could be exploited for crashes or potential code execution in the X server.

Vulnerability class: Buffer Overflow

Published 2026-10-28 · last modified 2026-10-28.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

CWE-122 — Heap-based Buffer Overflow

References

gitlab.freedesktop.org/xorg/xserver/-/commit/89101a6c6618f543d7502f2077c7ef1a50… (patch)

Frequently asked questions

What is CVE-2026-93518?: CVE-2026-93518 is a high-severity vulnerability in X.org Xorg-X11-Server, classified under Heap-based Buffer Overflow. CVSS score: 7.8/10. Published 2026-10-28.
How severe is CVE-2026-93518?: High severity. CVSS v3 base score is 7.8 out of 10.