As of this writing, (common hosts for .NET 4.0.30319) are out of extended support. While Microsoft offers ESU (Extended Security Updates) for paying customers, they do not issue new security patches for .NET 4.0 itself except through the .NET 4.8 upgrade.
Vulnerabilities such as MS10-070 allow attackers to decrypt and modify server-encrypted data or download sensitive files like web.config due to improper error handling during encryption padding. Deserialization Attacks:
By tricking a user into opening a malicious Microsoft Office document or visiting a compromised website, the attacker can execute arbitrary code with the privileges of the logged-in user. CVE-2014-4076: Elevation of Privilege (EoP)
CVE-2017-8759 (SOAP WSDL parser) — though originally .NET 3.5, similar deserialization flaws existed in .NET 4.0.30319 until patched in Oct 2017. microsoft net framework 4.0 v 30319 vulnerabilities
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319
If you see 4.0.30319 in a production environment today, it is to all patched .NET Framework issues from 2016 onward.
The Forms Authentication feature in .NET 4.0 has been identified as having a bypass vulnerability, allowing remote authenticated users to access arbitrary accounts using crafted usernames. Information Disclosure: As of this writing, (common hosts for
Legacy .NET XML parsers, such as XmlDocument and XmlTextReader in version 4.0, have dangerous default settings. By default, they allow the resolution of external inline DTDs (Document Type Definitions) and XML entities. Attackers can exploit this to read local server files, conduct Server-Side Request Forgery (SSRF), or cause Denial of Service (DoS) attacks. Insecure Default Cryptography
If code changes are possible but a full rewrite is not, audit the codebase to eliminate dangerous classes:
Can you check your via the Windows Registry? Deserialization Attacks: By tricking a user into opening
This critical bulletin from October 2010 specifically addressed a JIT compiler vulnerability that could allow remote code execution. The issue affected .NET Framework 4.0 on x64-based and Itanium-based Windows systems, with a severity rating of Critical for many affected platforms.
Before diving into vulnerabilities, it is crucial to understand what 4.0.30319 represents. This number is the and the assembly file version of the core libraries. Early versions of .NET 4.0 (RTM) had build numbers like 4.0.30319.1 (RTM) and later 4.0.30319.269 (with updates).
The security weaknesses in .NET Framework 4.0 generally fall into three major architectural categories. 1. Insecure Deserialization