CVE-2006-7197 in Tomcat
Summary
by MITRE
The AJP connector in Apache Tomcat 5.5.15 uses an incorrect length for chunks, which can cause a buffer over-read in the ajp_process_callback in mod_jk, which allows remote attackers to read portions of sensitive memory.
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Analysis
by VulDB Data Team • 07/14/2021
The vulnerability identified as CVE-2006-7197 represents a critical buffer over-read issue within the Apache Tomcat AJP connector implementation. This flaw exists in version 5.5.15 and affects the mod_jk module which facilitates communication between Apache HTTP Server and Tomcat. The vulnerability stems from improper handling of chunked data lengths during the AJP protocol processing, creating a scenario where memory boundaries are exceeded during data parsing operations.
The technical root cause lies in the ajp_process_callback function within mod_jk where the application fails to properly validate or calculate the length of data chunks received from the AJP connector. When Tomcat processes incoming AJP requests, it encounters malformed chunk length values that cause the buffer management logic to read beyond allocated memory boundaries. This improper memory access pattern creates a condition where attackers can potentially extract arbitrary memory contents, including sensitive data such as session tokens, application credentials, or internal system information.
From an operational perspective, this vulnerability presents significant security implications for web applications deployed on affected Tomcat versions. Remote attackers can exploit this flaw without authentication by sending specially crafted AJP requests that manipulate chunk length values. The over-read behavior allows attackers to gather information about the application's memory layout, potentially leading to further exploitation techniques including information disclosure attacks that could reveal system internals or application secrets. The vulnerability specifically targets the mod_jk integration point, making it particularly dangerous for environments using Apache HTTP Server as a reverse proxy in front of Tomcat instances.
The security impact of this vulnerability aligns with CWE-125, which describes out-of-bounds read conditions in software implementations. This flaw also maps to ATT&CK technique T1005, focusing on data from local system collection, as attackers can harvest sensitive information from memory contents. Additionally, the vulnerability demonstrates characteristics of T1555, which involves credential access through memory manipulation. Organizations using this version of Tomcat should immediately implement mitigations including upgrading to patched versions, implementing network segmentation, or applying firewall rules to restrict AJP traffic to trusted sources only. The vulnerability underscores the importance of proper input validation and memory boundary checking in protocol implementations, particularly in middleware components that handle data exchange between different application servers and web servers.