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Vulnerability record · CVE-2026-88806 · published 21 September 2026

CVE-2026-88806: Heap-based buffer overflow vulnerability

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

7.5 CVSS 3.1 High EPSS 0.20% · top 91.2% CWE-122 · Heap-based buffer overflow Awaiting Analysis
7.5CVSS 3.1 base score
0.20%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
1References
22 Sep 2026Last modified by NVD

Description

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

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

References

LinkTags
https://gitlab.freedesktop.org/xorg/lib/libx11/-/merge_requests/309

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Source: NIST National Vulnerability Database (record CVE-2026-88806), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.