CVE-2016-0706 in Tomcat
Summary
by MITRE
Apache Tomcat 6.x before 6.0.45, 7.x before 7.0.68, 8.x before 8.0.31, and 9.x before 9.0.0.M2 does not place org.apache.catalina.manager.StatusManagerServlet on the org/apache/catalina/core/RestrictedServlets.properties list, which allows remote authenticated users to bypass intended SecurityManager restrictions and read arbitrary HTTP requests, and consequently discover session ID values, via a crafted web application.
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Analysis
by VulDB Data Team • 07/08/2022
The vulnerability identified as CVE-2016-0706 represents a critical security flaw in Apache Tomcat versions prior to specific patch releases. This issue affects multiple major versions including 6.x before 6.0.45, 7.x before 7.0.68, 8.x before 8.0.31, and 9.x before 9.0.0.M2, creating a widespread impact across the Tomcat ecosystem. The vulnerability stems from improper configuration of security restrictions within the Tomcat container's servlet management system.
The technical flaw resides in the missing entry for StatusManagerServlet within the RestrictedServlets.properties file located in org/apache/catalina/core/ directory. This configuration oversight allows authenticated attackers to bypass the intended SecurityManager restrictions that should normally prevent access to sensitive internal servlets. The SecurityManager in Tomcat is designed to control access to potentially dangerous operations and internal components, but this particular misconfiguration creates an exploitable gap in the security model.
Remote authenticated users can exploit this vulnerability by crafting malicious web applications that leverage the improperly restricted servlet. The attack enables these users to read arbitrary HTTP requests that would normally be protected from external access. This capability directly exposes session ID values which are critical components for maintaining user authentication state across web applications. Session hijacking becomes possible when attackers can extract these identifiers, allowing them to impersonate legitimate users and gain unauthorized access to protected resources.
The operational impact of this vulnerability extends beyond simple information disclosure. Session ID exposure creates a pathway for session fixation attacks, where attackers can manipulate user sessions and potentially gain full administrative access to applications running on affected Tomcat instances. This vulnerability particularly affects web applications that rely heavily on session-based authentication mechanisms, making it a significant concern for enterprise environments and applications handling sensitive data.
The vulnerability aligns with CWE-284, which describes improper access control issues in software systems. From an adversarial perspective, this flaw maps to ATT&CK technique T1078.004, which covers valid accounts with restricted permissions being used to gain access to systems. Organizations should immediately implement mitigations including upgrading to patched versions of Tomcat, reviewing security configurations, and implementing additional monitoring for suspicious access patterns. The recommended remediation involves applying the appropriate patches for each affected major version, ensuring that the RestrictedServlets.properties file properly includes all necessary servlet entries, and conducting comprehensive security assessments of web applications running on affected Tomcat instances.