Executive brief
A security vulnerability has been identified in Windows Active Directory, the service responsible for managing users and permissions across a corporate network. An authorized user on the network could exploit this flaw to cause a denial-of-service, potentially disrupting authentication and access to company resources. This could lead to operational downtime as critical identity services become unavailable.
Technical details
An out-of-bounds read vulnerability (CWE-125) exists in Windows Active Directory. The flaw is triggered when the service improperly handles memory during the processing of specific network requests. An authenticated attacker with low privileges can exploit this over the network to cause a denial-of-service (DoS) condition or potentially read limited sensitive information from memory. Microsoft has released security updates to address this issue across affected versions of Windows 10, 11, and Windows Server.
Affected products
- Microsoft Windows 10 Version 21H2 10.0.19044.0 to 10.0.19044.7548
- Microsoft Windows 10 Version 22H2 10.0.19045.0 to 10.0.19045.7548
- Microsoft Windows 11 Version 24H2 10.0.26100.0 to 10.0.26100.8875
- Microsoft Windows 11 Version 25H2 10.0.26200.0 to 10.0.26200.8875
- Microsoft Windows 11 version 26H1 10.0.28000.0 to 10.0.28000.2269
- Microsoft Windows Server 2022 10.0.20348.0 to 10.0.20348.5386
- Microsoft Windows Server 2025 10.0.26100.0 to 10.0.26100.33158
Timeline
- 2026-07-14: advisory: Initial disclosure by Microsoft and NVD
- 2026-07-14: patched: Security updates released by Microsoft