Out-of-bounds Read in X.org Libx11

CVE-2026-94285

An out-of-bounds read in libX11's byte-oriented codeset parser in libX11 before 1.8.14 could be used by malicious X servers to crash attached X clients.

Vulnerability class: Buffer Overflow

Published .

CVSS v3 metric

CVSS v3 base score 5.1 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L.

EPSS exploit prediction

EPSS: 0.001 (1.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 1st percentile — 1.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-94285?
CVE-2026-94285 is a medium-severity vulnerability in X.org Libx11, classified under Out-of-bounds Read. CVSS score: 5.1/10. Published 2026-09-28.
How severe is CVE-2026-94285?
Medium severity. CVSS v3 base score is 5.1 out of 10.