CVE-2026-50304: Windows Active Directory Federation Services Denial of Service Vulnerability

Overview

Severity

High (CVSS 7.5)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C

Category

Denial of Service

Exploit Status

Not Exploited

Exploitation Likelihood

Unlikely

Patch Tuesday

2026-Jul

Released

2026-07-14

Description

Stack-based buffer overflow in Active Directory Federation Services allows an unauthorized attacker to deny service over a network.

FAQ

According to the CVSS metrics, successful exploitation of this vulnerability could lead to major loss of availability (A:H). What does that mean for this vulnerability? An attacker can send specially crafted packets which could affect availability of the service and result in Denial of Service (DoS).

Affected Products (15)

Windows

• Windows 10 Version 1809 for 32-bit Systems
• Windows 10 Version 1809 for x64-based Systems
• Windows Server 2019
• Windows Server 2019 (Server Core installation)
• Windows Server 2022
• Windows Server 2025 (Server Core installation)
• Windows Server 2025
• Windows 10 Version 1607 for 32-bit Systems
• Windows 10 Version 1607 for x64-based Systems
• Windows Server 2016
• Windows Server 2016 (Server Core installation)

ESU

• Windows Server 2012
• Windows Server 2012 (Server Core installation)
• Windows Server 2012 R2
• Windows Server 2012 R2 (Server Core installation)

Security Updates (6)

• 5099538
• 5099540
• 5099536
• 5099535
• 5099445
• 5099444

Acknowledgments

Anonymous

Revision History

• 2026-07-14: Information published.