CVE-2026-57976: Microsoft Active Directory Domain Services null pointer dereference

CVE-2026-57976 · Severity: medium · CVSS 6.5 · Published 2026-07-14

A security vulnerability has been identified in Microsoft Active Directory Domain Services, the core service used by organizations to manage users, computers, and network permissions. An authorized user on the network could exploit this flaw to crash the service, leading to a denial-of-service condition. This would prevent users from logging in or accessing shared network resources, potentially disrupting business operations.

Technologies: Microsoft Active Directory Domain Services, Microsoft Windows 11, Microsoft Windows 10, Microsoft Windows Server 2012. Vendors: Microsoft.

Quick answers

Is CVE-2026-57976 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-57976 being exploited in the wild.
How severe is CVE-2026-57976?
Medium severity, with a CVSS score of 6.5, published 14 July 2026.
Which products and versions are affected?
Microsoft Windows 11 24H2, 25H2, 26H1; Microsoft Windows 10 1607, 1809, 21H2, 22H2; Microsoft Windows Server 2012 All editions including Server Core.
Is there a fix for CVE-2026-57976?
A patch was published on 2026-07-14: Security updates made available via Microsoft Security Update Guide Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-57976 attacked?
It is attacked over the network, in an operating system.
Am I affected by CVE-2026-57976?
Check whether you run Microsoft Active Directory Domain Services, Microsoft Windows 11, Microsoft Windows 10 or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A NULL pointer dereference (CWE-476) exists within Microsoft Active Directory Domain Services. An attacker with low-privileged domain credentials can trigger this vulnerability over the network without user interaction. Successful exploitation causes the affected service to crash, resulting in a denial-of-service (DoS) for authentication and directory lookup functions. The vulnerability affects multiple versions of Windows 10, Windows 11, and Windows Server 2012. Microsoft has released security updates to address this issue.

Affected products

  • Microsoft Windows 10 1607, 1809, 21H2, 22H2
  • Microsoft Windows 11 24H2, 25H2, 26H1
  • Microsoft Windows Server 2012 All editions including Server Core
  • Microsoft Active Directory Domain Services

Timeline

  • 2026-07-14: advisory: Initial advisory published by Microsoft and NVD
  • 2026-07-14: patched: Security updates made available via Microsoft Security Update Guide

References

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