Use After Free in Microsoft Windows_11_24h2
CVE-2026-20870
Use after free in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally.
Vulnerability class: Use-After-Free
EPSS: 0.004 (35.9th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Microsoft Windows_11_24h2
- Microsoft Windows_11_25h2
- Microsoft Windows 11 Version 24h2 — versions 10.0.26100.0
- Microsoft Windows 11 Version 25h2 — versions 10.0.26200.0
- Microsoft Windows Server 2025 — versions 10.0.26100.0
- Microsoft Windows_server_2025
- Microsoft Windows Server 2025 (Server Core Installation) — versions 10.0.26100.0
Weakness classification (CWE)
References
- secure@microsoft.com (vendor-advisory, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-20870?
- CVE-2026-20870 is a high-severity vulnerability in Microsoft Windows_11_24h2, classified under Use After Free. CVSS score: 7.8/10. Published 2026-01-13.
- How severe is CVE-2026-20870?
- High severity. CVSS v3 base score is 7.8 out of 10.