Use-after-free in Microsoft Windows and Windows Server - CVE-2026-50459

Vulnerability identifier: #VU137869

CSH Severity: Low

CVSS v4: 7.1 [CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-50459

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a local attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in Windows Kernel. A local attacker can gain elevated privileges on the target system.

Microsoft Windows
Windows Server

Install updates from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7548, 10 22H2 10.0.19045.7548, 11 24H2 10.0.26100.8875, 11 25H2 10.0.26200.8875, 11 26H1 10.0.28000.2269, 11 26H1 10.0.28000.2525
Windows Server - addressed in versions 2012 R2 6.3.9600.23291, 2022 10.0.20348.5386, 2025 10.0.26100.33158

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50459

• Multiple vulnerabilities in Microsoft Windows Kernel