CVE-2026-54119: Microsoft Windows Active Directory infinite loop denial of service

CVE-2026-54119 · Severity: high · CVSS 7.5 · Published 2026-07-14

A vulnerability in Windows Active Directory, the central service used to manage users and computers on a corporate network, could allow an attacker to crash the system. By sending a specially crafted request over the network, an unauthorized user can trigger an infinite loop that makes the directory service unresponsive. This results in a denial-of-service, preventing employees from logging in or accessing network resources.

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

Quick answers

Is CVE-2026-54119 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-54119 being exploited in the wild.
How severe is CVE-2026-54119?
High severity, with a CVSS score of 7.5, published 14 July 2026.
Which products and versions are affected?
Microsoft Windows 11 Version 24H2, 25H2, 26H1; Microsoft Windows 10 Version 1607, 1809, 21H2, 22H2; Microsoft Windows Server 2012 All versions including Server Core.
Is there a fix for CVE-2026-54119?
A patch was published on 2026-07-14: Security updates released by Microsoft Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-54119 attacked?
It is attacked over the network, in an operating system.
Am I affected by CVE-2026-54119?
Check whether you run Microsoft Active Directory, 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 denial-of-service vulnerability exists in Windows Active Directory due to an infinite loop (CWE-835) triggered by an unreachable exit condition. An unauthenticated attacker can exploit this by sending a malicious request over the network to an affected Active Directory instance. Successful exploitation causes the service to hang or become unresponsive, leading to a complete loss of availability for directory services. 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 Version 1607, 1809, 21H2, 22H2
  • Microsoft Windows 11 Version 24H2, 25H2, 26H1
  • Microsoft Windows Server 2012 All versions including Server Core
  • Microsoft Windows Active Directory

Timeline

  • 2026-07-14: advisory: Initial publication by Microsoft and NVD
  • 2026-07-14: patched: Security updates released by Microsoft

References

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