vulnerability
Red Hat: CVE-2026-33999: xorg: xwayland: X.Org X server: Denial of Service via integer underflow in XKB compatibility map handling (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:L/AC:L/Au:S/C:C/I:C/A:C) | Apr 23, 2026 | Apr 29, 2026 | May 6, 2026 |
Severity
7
CVSS
(AV:L/AC:L/Au:S/C:C/I:C/A:C)
Published
Apr 23, 2026
Added
Apr 29, 2026
Modified
May 6, 2026
Description
A flaw was found in the X.Org X server. This integer underflow vulnerability, specifically in the XKB compatibility map handling, allows an attacker with local or remote X11 server access to trigger a buffer read overrun. This can lead to memory-safety violations and potentially a denial of service (DoS) or other severe impacts.
Solutions
redhat-upgrade-tigervncredhat-upgrade-tigervnc-debuginforedhat-upgrade-tigervnc-debugsourceredhat-upgrade-tigervnc-iconsredhat-upgrade-tigervnc-licenseredhat-upgrade-tigervnc-selinuxredhat-upgrade-tigervnc-serverredhat-upgrade-tigervnc-server-debuginforedhat-upgrade-tigervnc-server-minimalredhat-upgrade-tigervnc-server-minimal-debuginforedhat-upgrade-tigervnc-server-moduleredhat-upgrade-tigervnc-server-module-debuginforedhat-upgrade-xorg-x11-server-commonredhat-upgrade-xorg-x11-server-debuginforedhat-upgrade-xorg-x11-server-debugsourceredhat-upgrade-xorg-x11-server-develredhat-upgrade-xorg-x11-server-sourceredhat-upgrade-xorg-x11-server-xdmxredhat-upgrade-xorg-x11-server-xdmx-debuginforedhat-upgrade-xorg-x11-server-xephyrredhat-upgrade-xorg-x11-server-xephyr-debuginforedhat-upgrade-xorg-x11-server-xnestredhat-upgrade-xorg-x11-server-xnest-debuginforedhat-upgrade-xorg-x11-server-xorgredhat-upgrade-xorg-x11-server-xorg-debuginforedhat-upgrade-xorg-x11-server-xvfbredhat-upgrade-xorg-x11-server-xvfb-debuginforedhat-upgrade-xorg-x11-server-xwaylandredhat-upgrade-xorg-x11-server-xwayland-debuginforedhat-upgrade-xorg-x11-server-xwayland-debugsourceredhat-upgrade-xorg-x11-server-xwayland-devel
References
Rapid7 Labs
2026 Global Threat Landscape Report
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