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CVE-2023-6816

critical

A flaw was found in X.Org server.

Vendor / product: X.org — x server

A flaw was found in X.Org server. Both DeviceFocusEvent and the XIQueryPointer reply contain a bit for each logical button currently down. Buttons can be arbitrarily mapped to any value up to 255, but the X.Org Server was only allocating space for the device's particular number of buttons, leading to a heap overflow if a bigger value was used.

CVSS
9.8
9.8 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2024-01-18 05:15
Modified: 2026-11-04 21:17
NVD status: Modified
Last synced 4 hours ago
Verified against the source API 2026-11-04 21:37 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

x.org / x_server <21.1.11
x.org / xwayland <23.2.4
fedoraproject / fedora 39
redhat / enterprise_linux_desktop 7.0
redhat / enterprise_linux_server 7.0
redhat / enterprise_linux_workstation 7.0
debian / debian_linux 10.0

Weakness classification (CWE)

CWE-787

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

Data sources

NVD CVE API 2.0 — fetched 2026-11-04 21:37 UTC · record ↗

Learn the basics

Understanding CVEs and CVSS Scores

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