CVE-2014-4149 in .NET Framework
Summary
by MITRE
Microsoft .NET Framework 1.1 SP1, 2.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly perform TypeFilterLevel checks, which allows remote attackers to execute arbitrary code via crafted data to a .NET Remoting endpoint, aka "TypeFilterLevel Vulnerability."
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Analysis
by VulDB Data Team • 12/16/2024
The CVE-2014-4149 vulnerability represents a critical security flaw in Microsoft .NET Framework versions spanning from 1.1 SP1 through 4.5.2, where the TypeFilterLevel validation mechanism fails to properly enforce security restrictions. This vulnerability specifically targets the .NET Remoting infrastructure, which enables distributed applications to communicate across process and machine boundaries through serialized objects. The flaw stems from insufficient validation of TypeFilterLevel settings that should restrict the types of objects that can be deserialized during remote procedure calls, creating an avenue for malicious code execution.
The technical exploitation of this vulnerability occurs when a remote attacker crafts specially designed serialized data that bypasses the intended TypeFilterLevel restrictions. This allows attackers to inject and execute arbitrary code on systems running vulnerable .NET Framework versions, as the deserialization process fails to validate the types of objects being reconstructed. The vulnerability operates at the core of .NET's serialization mechanism, where objects are converted to a format suitable for transmission over networks and then reconstructed on the receiving end. When TypeFilterLevel checks are circumvented, attackers can leverage this to execute malicious payloads that would normally be blocked by the framework's security controls.
The operational impact of CVE-2014-4149 extends significantly across enterprise environments, as .NET Remoting is widely used in distributed applications, web services, and enterprise applications. Attackers can exploit this vulnerability to gain unauthorized access to systems, escalate privileges, and potentially establish persistent access points within networks. The vulnerability's reach is particularly concerning because it affects multiple versions of the .NET Framework, meaning organizations with legacy systems or applications that have not been updated may remain vulnerable. This creates a substantial attack surface that can be leveraged for lateral movement, data exfiltration, and system compromise.
Organizations should implement immediate mitigations including applying the relevant Microsoft security updates, disabling .NET Remoting where possible, and implementing network segmentation to limit exposure. The vulnerability aligns with CWE-502, which addresses deserialization of untrusted data, and corresponds to techniques described in the MITRE ATT&CK framework under T1059 for command and script injection. Security teams should also consider implementing application whitelisting policies and monitoring for suspicious deserialization activities. The remediation process requires careful assessment of applications that rely on .NET Remoting functionality, as disabling the feature entirely may impact legacy systems. Organizations should prioritize patch management processes and consider implementing additional security controls such as runtime application protection to prevent exploitation of similar vulnerabilities in the future.