Name: CVE-2026-56000: Use After Free
Creator: Rapid7
Published: 2026-07-08T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-56000, CWE-416, CVSS 7.8, EPSS 0.00214

Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a Heap Use After Free, due to CommonMakeCurrent() pointing into potentially reallocated memory.

CVSS Details

CVSS 4.0 Base Score: 9 (CRITICAL)
CVSS 4.0 Vector: (CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
CVSS 3.1 Base Score: 7.8
CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alma_linux	—	Upgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-Xwayland-devel	Oct 11, 2026	Jul 13, 2026
Alpine Linux	—	Upgrade xwaylandUpgrade xorg-server	Jul 9, 2026	Jul 8, 2026
Amazon_linux_2023	—	Upgrade xorg-x11-server-Xwayland-develUpgrade xorg-x11-server-Xwayland-debuginfoUpgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-Xwayland-debugsource	Jul 21, 2026	Jul 8, 2026
Debian	—	Upgrade xorg-server	Sep 21, 2026	Jul 8, 2026
Freebsd	—	Upgrade xwaylandUpgrade xorg-server	Jul 9, 2026	Jul 8, 2026
Gentoo Linux	—	Upgrade x11-base/xwayland.Upgrade x11-base/xorg-server.	Aug 17, 2026	Aug 17, 2026
Oracle_linux	—	Upgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-Xwayland-devel	Oct 22, 2026	Jul 8, 2026
Redhat_linux	—	Upgrade xorg-x11-server-Xwayland-debuginfoUpgrade xorg-x11-server-Xwayland-develNo solution existsUpgrade xorg-x11-server-Xwayland-debugsourceUpgrade xorg-x11-server-Xwayland	Jul 14, 2026	Jul 8, 2026
Rocky_linux	—	Upgrade xorg-x11-server-Xwayland-develUpgrade xorg-x11-server-Xwayland-debuginfoUpgrade xorg-x11-server-XwaylandUpgrade xorg-x11-server-Xwayland-debugsource	Jul 16, 2026	Jul 14, 2026

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CVSS Details

Covered by Rapid7

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