Use-after-free in X.org Server - CVE-2026-93536

Vulnerability identifier: #VU157678

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-93536

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to compromise vulnerable system.

The vulnerability exists due to a use-after-free error within the handling of Window objects. A local user can gain access to sensitive information on the target system.

X.org Server
Anolis OS
Fedora
xorg-x11-server
xorg-x11-server-Xwayland
xorg-x11-server-Xwayland-devel
xorg-x11-server-Xwayland-doc

Install updates from vendor's website.

xorg-x11-server - addressed in versions 21.1.25-1.fc44, 21.1.25-1.fc45, 21.1.25-2.fc44, 21.1.25-2.fc45
xorg-x11-server-Xwayland - update to 23.2.5-13
xorg-x11-server-Xwayland-devel - update to 23.2.5-13
xorg-x11-server-Xwayland-doc - update to 23.2.5-13
xorg-x11-server-Xwayland - addressed in versions 24.1.14-1.fc43, 24.1.14-1.fc44, 24.1.14-1.fc45

• https://www.zerodayinitiative.com/advisories/ZDI-26-780/

• Multiple vulnerabilities in X.Org Server
• Fedora 45 update for xorg-x11-server
• Fedora 44 update for xorg-x11-server
• Fedora 45 update for xorg-x11-server-Xwayland
• Fedora 44 update for xorg-x11-server-Xwayland
• Fedora 43 update for xorg-x11-server-Xwayland
• Fedora 45 update for xorg-x11-server
• Fedora 44 update for xorg-x11-server
• Anolis OS update for xorg-x11-server-Xwayland