CVE-2026-83781 Windows Program Compatibility Assistant Service Elevation of Privilege Vulnerability
An authorized local attacker can elevate privileges due to improper null termination in the Windows Program Compatibility Assistant Service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-83781?
CVE-2026-83781 is a high-severity vulnerability in Microsoft Windows 11 Version 23H2, published on 13 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Improper null termination in Windows Program Compatibility Assistant Service allows an authorized attacker to elevate privileges locally.
Weakness: CWE-170
Which versions are affected by CVE-2026-83781?
How do I fix CVE-2026-83781?
No fix has been published for CVE-2026-83781 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-83781 being exploited?
There is no known exploitation of CVE-2026-83781 in the wild and no public exploit code.
Sources
Also known as GHSA-vmxj-c2f6-mf32.