CVE-2026-20854 Windows Local Security Authority Subsystem Service (LSASS) Remote Code Execution Vulnerability
An authorized attacker can execute code remotely via a use-after-free flaw in the Windows Local Security Authority Subsystem Service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-20854?
CVE-2026-20854 is a high-severity use after free vulnerability in Microsoft Windows 11 24h2, published on 13 Jan 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Use after free in Windows Local Security Authority Subsystem Service (LSASS) allows an authorized attacker to execute code over a network.
Weakness: CWE-416
Which versions are affected by CVE-2026-20854?
It affects 3 products.
Products include Microsoft Windows 11 24h2, Microsoft Windows 11 25h2, Microsoft Windows Server 2025.
How do I fix CVE-2026-20854?
No fix has been published for CVE-2026-20854 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-20854 being exploited?
There is no known exploitation of CVE-2026-20854 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Windows 11 24h2
- CVE-2025-60710 Microsoft Windows Link Following
- CVE-2026-54990 Remote Desktop Client Remote Code Execution Vulnerability
- CVE-2025-50165 Windows Graphics Component Remote Code Execution Vulnerability
- CVE-2025-21311 Windows NTLM V1 Elevation of Privilege Vulnerability
- CVE-2026-108463 Windows SmartScreen Security Feature Bypass Vulnerability
Sources
Also known as GHSA-7g73-j999-7mq6.