CVE-2014-4072 in .NET Framework
Summary
by MITRE
Microsoft .NET Framework 1.1 SP1, 2.0 SP2, 3.0 SP2, 3.5, 3.5.1, 4, 4.5, 4.5.1, and 4.5.2 does not properly use a hash table for request data, which allows remote attackers to cause a denial of service (resource consumption and ASP.NET performance degradation) via crafted requests, aka ".NET Framework Denial of Service Vulnerability."
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Analysis
by VulDB Data Team • 12/16/2024
The vulnerability identified as CVE-2014-4072 represents a critical denial of service flaw within Microsoft .NET Framework versions spanning from 1.1 SP1 through 4.5.2. This weakness specifically manifests in the improper handling of hash table structures used for processing HTTP request data within the ASP.NET runtime environment. The flaw exploits a fundamental design issue in how the framework manages request data structures, creating conditions where maliciously crafted requests can trigger excessive resource consumption patterns that ultimately degrade system performance or cause complete service unavailability.
The technical root cause of this vulnerability lies in the hash table implementation within the .NET Framework's request processing pipeline. When processing HTTP requests containing specially crafted data, the framework's hash table collision handling mechanism becomes inefficient, leading to increased computational overhead and memory consumption. This occurs because the hash table's internal structure fails to properly manage key collisions, causing the system to expend excessive processing cycles on resolving hash conflicts. The vulnerability operates at the application layer and can be exploited through HTTP requests that contain malformed or specially constructed parameters designed to trigger the problematic hash table behavior.
From an operational impact perspective, this vulnerability enables remote attackers to perform denial of service attacks against .NET Framework applications without requiring authentication or elevated privileges. The attack effectiveness is particularly concerning because it can target any ASP.NET application running on affected framework versions, regardless of the application's specific configuration or security hardening measures. The resource consumption patterns created by this vulnerability can lead to significant performance degradation, application unresponsiveness, or complete service interruption, making it a serious concern for web applications and services that rely on .NET Framework infrastructure.
The vulnerability aligns with CWE-400, which catalogs "Uncontrolled Resource Consumption" as a common weakness in software systems, and demonstrates characteristics consistent with the ATT&CK technique T1499.004, "Endpoint Denial of Service," where adversaries target application endpoints to consume system resources and cause service disruption. Organizations running affected .NET Framework versions face significant risk exposure, as the vulnerability can be exploited through standard web traffic without requiring specialized tools or access credentials. The attack surface is extensive given that the vulnerability affects multiple framework versions and can impact any ASP.NET application regardless of its specific implementation or security controls.
Mitigation strategies for this vulnerability include applying the official Microsoft security updates and patches released for the affected framework versions. Organizations should prioritize patching their .NET Framework installations to address the hash table implementation issues that trigger the resource consumption patterns. Additionally, implementing network-level controls such as rate limiting and request filtering can help reduce the impact of potential attacks by limiting the volume of requests that can be processed within specific time periods. Application-level protections including input validation and request normalization can also help minimize exposure, though these measures do not fully address the underlying framework vulnerability and should be combined with proper patch management for comprehensive protection.