Incorrect authorization in Microsoft Windows and Windows Server - CVE-2026-119821

Vulnerability details

The vulnerability allows a local user to elevate privileges and potentially intercept or modify network traffic belonging to other Windows services.

The vulnerability exists due to improper authorization in Windows Network Connection Broker when managing access to network connections owned by Windows services. A local user can gain unauthorized access to connections owned by other services to potentially intercept or modify traffic using those connections.

Affected software

How to mitigate CVE-2026-119821

External References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-119821
• https://support.microsoft.com/help/5131291

Related Security Bulletins

• Multiple vulnerabilities in Microsoft Windows