CVE-2012-0881 in Transportation Management
Summary
by MITRE
Apache Xerces2 Java Parser before 2.12.0 allows remote attackers to cause a denial of service (CPU consumption) via a crafted message to an XML service, which triggers hash table collisions.
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Analysis
by VulDB Data Team • 10/04/2024
The vulnerability identified as CVE-2012-0881 affects the Apache Xerces2 Java Parser version 2.11.0 and earlier, representing a significant security flaw that enables remote attackers to execute denial of service attacks through carefully crafted XML messages. This vulnerability specifically targets the parser's handling of hash tables during XML processing, creating a condition where malicious input can trigger excessive CPU consumption and system resource exhaustion. The flaw exists in the parser's internal data structure management, particularly in how it processes and stores XML elements within hash tables, making it susceptible to hash collision attacks that can be exploited remotely without requiring authentication or special privileges.
The technical implementation of this vulnerability stems from the parser's use of a hash table data structure to store and manage XML element information during parsing operations. When an attacker crafts a malicious XML message containing specially designed elements that cause hash collisions, the parser's hash table implementation becomes inefficient, leading to degraded performance and eventual system resource exhaustion. This behavior manifests as excessive CPU utilization as the parser attempts to resolve hash conflicts, effectively consuming system resources and rendering the service unavailable to legitimate users. The vulnerability operates at the application layer and can be exploited against any XML service that utilizes the affected Apache Xerces2 parser version, making it particularly dangerous in web applications and services that process untrusted XML input.
The operational impact of CVE-2012-0881 extends beyond simple service disruption, as it can be leveraged to create sustained denial of service conditions that may require system restarts to resolve. Attackers can craft XML messages that specifically target the hash table collision mechanism, causing the parser to consume increasing amounts of CPU cycles and memory resources over time. This vulnerability is particularly concerning because it can be exploited through standard XML processing channels, including web services, XML-based APIs, and any application that relies on the affected parser for XML document handling. The resource exhaustion can lead to complete service unavailability, impacting business operations and potentially affecting downstream systems that depend on the vulnerable service.
Mitigation strategies for CVE-2012-0881 primarily involve upgrading to Apache Xerces2 Java Parser version 2.12.0 or later, which includes fixes that address the hash table collision vulnerability. Organizations should also implement input validation and sanitization measures to filter potentially malicious XML content before it reaches the parser, though this approach provides only partial protection. Network-level protections such as rate limiting and resource monitoring can help detect and prevent exploitation attempts, while application-level defenses including XML parser configuration adjustments and resource quotas can limit the impact of successful attacks. This vulnerability aligns with CWE-400, which classifies it as a weakness related to unspecified resource exhaustion, and maps to ATT&CK technique T1499.004 for denial of service attacks. System administrators should also consider implementing intrusion detection systems that can identify patterns associated with hash collision attacks and establish monitoring protocols to detect unusual CPU consumption patterns that may indicate exploitation attempts.