CVE-2026-83781: Windows Program Compatibility Assistant Service Elevation of Privilege Vulnerability
Improper null termination in Windows Program Compatibility Assistant Service allows an authorized attacker to elevate privileges locally.
Other sources
Windows Program Compatibility Assistant Service Elevation of Privilege Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.28000.3231Patch KB5127646 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7652Patch KB5126653 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26200.9711Patch KB5127648 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5761Patch KB5126655 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.33650Patch KB5126646 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26300.9711Patch KB5127648
Event History
Frequently Asked Questions
What level of access does an attacker need?
An attacker must already have local access and be authorized with low privileges. The attack does not require user interaction.
Is this exposed to unauthenticated remote attackers?
The available vector is local, so the provided data does not indicate unauthenticated remote exploitation.
Which Windows products are identified as affected?
The affected software list includes Microsoft Windows 11, Microsoft Windows Server 2022, and Microsoft Windows Server 2025.