The version number 4.0.30319 does not refer to a single vulnerable software version, but rather to the Common Language Runtime (CLR) 4.0, which serves as the foundational engine for all .NET Framework versions from 4.0 through 4.8.1. While the runtime version string remains static, the underlying framework receives continuous security patches through Windows Update. Vulnerability Landscape
Severity: 8.2 (High)
Vector: Remote Code Execution microsoft net framework 4.0 v 30319 vulnerabilities
False Positives: Vulnerability scanners often flag "4.0.30319" because it is the CLR version for all .NET 4.x releases, including the currently supported Microsoft .NET Framework 4.8. The version number 4
Perhaps the most alarming finding is CVE-2020-1046 (and its variants), which affects the way v4.0.30319 handles URL redirects in the HttpWebRequest object. By combining this with a lack of proper TLS certificate validation in older builds, an attacker performing a man-in-the-middle (MitM) attack could redirect a .NET application to a malicious update server or a UNC path (\\evil\share\malicious.dll) leading to RCE. GDI+ and WPF image parsing RCE via TIFF, EMF, etc
CVE-2015-2504: Improper object counting before array copies can lead to memory corruption and code execution via malicious XAML browser applications. Authentication Bypass:
Microsoft-Windows-DotNETRuntimeMicrosoft-Windows-DotNETRuntimeRundown