HIGH 7.5 Microsoft
CVE-2026-21218
.NET Spoofing Vulnerability
Microsoft Security Update 2026-Feb: .NET Spoofing Vulnerability
Affected Products
- .NET 10.0 installed on Mac OS
- .NET 10.0 installed on Windows
- .NET 8.0 installed on Linux
- .NET 8.0 installed on Windows
- .NET 10.0 installed on Linux
- .NET 8.0 installed on Mac OS
- .NET 9.0 installed on Mac OS
- .NET 9.0 installed on Linux
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21218
- https://nvd.nist.gov/vuln/detail/CVE-2026-21218
This high severity vulnerability with a CVSS score of 7.5 was published on 2026-02-10 via Microsoft. Affected: .NET 10.0 installed on Mac OS, .NET 10.0 installed on Windows, .NET 8.0 installed on Linux and 5 more.
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