CVE-2018-8421: Microsoft .NET Framework

Critical severity, CVSS 9.8. EPSS: 29.1% chance of exploitation in the next 30 days.

A remote code execution vulnerability exists when Microsoft .NET Framework processes untrusted input, aka ".NET Framework Remote Code Execution Vulnerability." This affects Microsoft .NET Framework 4.6, Microsoft .NET Framework 3.5, Microsoft .NET Framework 4.7/4.7.1/4.7.2, Microsoft .NET Framework 3.0, Microsoft .NET Framework 3.5.1, Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2, Microsoft .NET Framework 4.5.2, Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.1/4.7.2, Microsoft .NET Framework 4.7.1/4.7.2, Microsoft .NET Framework 4.7.2, Microsoft .NET Framework 2.0.

Affected products

• Microsoft .NET Framework: version 2.0 only; version 3.0 only; version 3.5 only; version 3.5.1 only; version 4.5.2 only; version 4.6 only; …

Published 2018-09-13. Last modified 2026-06-17.