CVE-2025-21193 Active Directory Federation Server Spoofing Vulnerability
Attackers can spoof Active Directory Federation Services requests, potentially bypassing security controls in Windows Server environments.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-21193?
CVE-2025-21193 is a medium-severity vulnerability in Microsoft Windows Server 2016, published on 14 Jan 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Active Directory Federation Server Spoofing Vulnerability
Weakness: CWE-352
Which versions are affected by CVE-2025-21193?
It affects 5 products.
Products include Microsoft Windows Server 2016, Microsoft Windows Server 2019, Microsoft Windows Server 2022, Microsoft Windows Server 2022 23h2, Microsoft Windows Server 2025.
How do I fix CVE-2025-21193?
No fix has been published for CVE-2025-21193 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-21193 being exploited?
There is no known exploitation of CVE-2025-21193 in the wild and no public exploit code.
Other vulnerabilities in Microsoft Windows Server 2016
- CVE-2021-34458 Windows Kernel Remote Code Execution Vulnerability
- CVE-2024-38076 Windows Remote Desktop Licensing Service Remote Code Execution Vulnerability
- CVE-2026-27928 Windows Hello Security Feature Bypass Vulnerability
- CVE-2025-27482 Windows Remote Desktop Services Remote Code Execution Vulnerability
- CVE-2024-49106 Windows Remote Desktop Services Remote Code Execution Vulnerability
Sources
Also known as GHSA-4wgp-9wjx-2m53.