CVE-2013-3133 in .NET Framework
Summary
by MITRE
Microsoft .NET Framework 2.0 SP2, 3.5, 3.5.1, 4, and 4.5 does not properly check the permissions of objects that use reflection, which allows remote attackers to execute arbitrary code via (1) a crafted XAML browser application (XBAP) or (2) a crafted .NET Framework application, aka "Anonymous Method Injection Vulnerability."
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Analysis
by VulDB Data Team • 05/18/2021
The CVE-2013-3133 vulnerability represents a critical permission checking flaw within Microsoft .NET Framework versions 2.0 SP2, 3.5, 3.5.1, 4, and 4.5 that fundamentally undermines the security model of the framework. This vulnerability specifically targets the reflection mechanisms used by .NET applications, creating a pathway for attackers to bypass security restrictions that should prevent arbitrary code execution. The flaw stems from insufficient validation of object permissions during reflection operations, allowing malicious actors to exploit this weakness through carefully crafted application payloads.
The technical implementation of this vulnerability leverages the Anonymous Method Injection attack vector, where attackers can manipulate reflection-based code execution to inject malicious methods into trusted application contexts. This occurs because the .NET Framework fails to properly validate the security context of objects when they are accessed through reflection APIs, particularly in scenarios involving XAML Browser Applications and .NET Framework applications. The vulnerability is particularly dangerous because it operates at a fundamental level of the framework's security architecture, affecting the core permission model that governs code execution boundaries.
From an operational perspective, this vulnerability creates significant risks for organizations running affected .NET Framework versions, as it enables remote code execution without requiring elevated privileges or specific user interactions. Attackers can craft malicious XBAP applications or .NET Framework applications that exploit the reflection permission checking flaw to execute arbitrary code on target systems. The impact extends beyond individual system compromise to potentially enable lateral movement within networks, as attackers can leverage this vulnerability to establish persistent access or escalate privileges. This vulnerability directly maps to CWE-264, which addresses permissions, privileges, and access controls, and aligns with ATT&CK technique T1059.001 for command and scripting interpreter and T1068 for exploit for privilege escalation.
The exploitation of CVE-2013-3133 requires attackers to create malicious applications that can manipulate reflection APIs to bypass security restrictions. This typically involves crafting XAML files or .NET assemblies that contain malicious code which, when executed, leverages the reflection permission flaw to gain elevated privileges. The vulnerability affects both client-side applications and server-side deployments, making it particularly concerning for enterprise environments where .NET Framework is widely deployed. Organizations must understand that this vulnerability can be exploited through various attack vectors including web-based attacks, email attachments, or malicious software downloads that utilize the affected framework versions.
Mitigation strategies for CVE-2013-3133 should include immediate deployment of Microsoft security patches and updates, particularly for the affected .NET Framework versions. System administrators should implement strict code access security policies and ensure that applications running on affected frameworks have minimal required permissions. Network segmentation and application whitelisting can provide additional protection layers, while monitoring for unusual reflection-based activity can help detect exploitation attempts. Organizations should also consider implementing runtime application self-protection measures and regularly review their .NET Framework deployment configurations to ensure that security controls are properly enforced. The vulnerability demonstrates the critical importance of maintaining up-to-date security patches and highlights the risks associated with legacy framework versions that may not receive continued security support.