CVE-2026-96222 ยท GHSA-vrv5-2jg9-4mmr
Microsoft Security Advisory CVE-2026-96222 - .NET Spoofing Vulnerability
- Risk score
- 69/100
- CVSS
- 7.4 v3.1
- Exploit chance (30 days)
- 0.6%
- Published
- 13 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- Improper certificate validation in Active Directory Federation Services (AD FS) allows an unauthorized attacker to perform spoofing over a network.
- Affected
- System.Security.Cryptography.Xml (nuget) >= 8.0.0, <= 8.0.4
- Fix
- Upgrade System.Security.Cryptography.Xml to 8.0.5 or later.
- Exploitation
- No known exploitation
Why it is Amber
- CVSS 7.4 high
- Remotely exploitable without logging in
- On your watchlist: .net, windows server, NuGet
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| System.Security.Cryptography.Xml | nuget | >= 8.0.0, <= 8.0.4 | 8.0.5 |
References
- https://github.com/advisories/GHSA-vrv5-2jg9-4mmr
- https://github.com/dotnet/runtime/security/advisories/GHSA-vrv5-2jg9-4mmr
- https://github.com/dotnet/announcements/issues/474
- https://github.com/dotnet/runtime/issues/135705
- https://nvd.nist.gov/vuln/detail/CVE-2026-96222
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-96222
- https://github.com/advisories/GHSA-vrv5-2jg9-4mmr
Original description
Improper certificate validation in Active Directory Federation Services (AD FS) allows an unauthorized attacker to perform spoofing over a network.
Last activity 13 Oct 2026. Patch Forecast updates every hour.