CVE-2026-96222 Active Directory Federation Services (AD FS) Spoofing Vulnerability
An attacker can spoof identities in Active Directory Federation Services due to improper certificate validation, bypassing security controls.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-96222?
CVE-2026-96222 is a high-severity vulnerability in Microsoft .Net, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Improper certificate validation in Active Directory Federation Services (AD FS) allows an unauthorized attacker to perform spoofing over a network.
Weakness: CWE-295
Which versions are affected by CVE-2026-96222?
4 open source packages ship an affected version, including System.Security.Cryptography.Xml, dotnet and dotnet-sdk. It affects 11 products.
| Package | Affected | Fixed in |
|---|---|---|
System.Security.Cryptography.Xml NuGet | From 8.0.0 | 8.0.5 |
System.Security.Cryptography.Xml NuGet | From 8.0.0 | 8.0.5 |
dotnet Bitnami | From 8.0.0 | 8.0.5 |
dotnet-sdk Bitnami | From 8.0.0 | 8.0.5 |
Products include Microsoft .Net, Microsoft .Net Framework, Microsoft Visual Studio 2022, Microsoft Visual Studio 2026, Microsoft Windows 10 1607, Microsoft Windows 10 1809 and 5 more.
How do I fix CVE-2026-96222?
Upgrade System.Security.Cryptography.Xml to 8.0.5 or later.
Is CVE-2026-96222 being exploited?
There is no known exploitation of CVE-2026-96222 in the wild and no public exploit code.
Other vulnerabilities in Microsoft .Net
- CVE-2024-43498 .NET and Visual Studio Remote Code Execution Vulnerability
- CVE-2024-0057 NET, .NET Framework, and Visual Studio Security Feature Bypass Vulnerability
- CVE-2026-96957 .NET Security Feature Bypass Vulnerability
- CVE-2026-69439 .NET and Visual Studio Elevation of Privilege Vulnerability
- CVE-2026-71328 .NET and Visual Studio Remote Code Execution Vulnerability
Sources
Also known as BIT-dotnet-2026-96222, BIT-dotnet-sdk-2026-96222, ECHO-e782-b942-c9ee, GHSA-vrv5-2jg9-4mmr, MINI-7h3g-hmmq-cx39, MINI-g72r-ph6p-v357 and 2 more.