CVE-2026-21218: Microsoft .net

High severity, CVSS 7.5. EPSS: 1% chance of exploitation in the next 30 days.

Improper handling of missing special element in .NET allows an unauthorized attacker to perform spoofing over a network.

Affected products

• Microsoft .net: from 8.0.0, before 8.0.24 (fixed in 8.0.24); from 9.0.0, before 9.0.13 (fixed in 9.0.13); from 10.0.0, before 10.0.3 (fixed in 10.0.3)

Published 2026-02-10. Last modified 2026-06-17.