CVE-2006-6915 in AIX
Summary
by MITRE
ftpd in IBM AIX 5.2.0 and 5.3.0 allows remote authenticated users to cause a denial of service (port exhaustion) via unspecified vectors. NOTE: some details were obtained from third party sources.
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Analysis
by VulDB Data Team • 07/13/2019
The vulnerability identified as CVE-2006-6915 affects the ftpd service running on IBM AIX operating systems version 5.2.0 and 5.3.0. This represents a significant security flaw that enables remote authenticated attackers to exploit a denial of service condition through unspecified vectors that lead to port exhaustion. The issue specifically targets the File Transfer Protocol daemon component that serves as the primary interface for file transfer operations within the AIX environment. Given that the vulnerability operates at the network service level, it presents a substantial risk to system availability and operational continuity for organizations relying on these older AIX versions. The authentication requirement for exploitation indicates that while the attack vector is accessible to legitimate users, it requires proper credentials to initiate the malicious activity, which complicates the threat landscape by involving authorized personnel.
The technical flaw manifests through mechanisms that cause the ftpd service to consume available network ports excessively, ultimately leading to port exhaustion conditions that prevent new connections from being established. This type of vulnerability falls under the category of resource exhaustion attacks where the attacker leverages legitimate service functionality to consume system resources beyond acceptable limits. The unspecified vectors suggest that the exploitation method could involve various approaches such as repeated connection attempts, improper connection handling, or manipulation of session management parameters within the FTP protocol implementation. The vulnerability demonstrates poor resource management practices within the IBM AIX ftpd implementation, where connection state tracking and port allocation mechanisms fail to properly handle abnormal usage patterns or malicious inputs from authenticated users.
From an operational impact perspective, this vulnerability creates severe availability issues for systems running affected IBM AIX versions, potentially disrupting critical file transfer operations and business processes that depend on FTP services. The port exhaustion condition means that legitimate users may experience service interruptions when attempting to establish new FTP connections, leading to productivity losses and potential business disruptions. Organizations using these older AIX versions face particular risk since the vulnerability affects core network services that are fundamental to system operations. The impact extends beyond simple service disruption to include potential cascading effects on dependent systems that rely on successful FTP operations for data exchange and synchronization. This vulnerability represents a significant concern for enterprise environments where FTP services are heavily utilized for system administration, data backup operations, and inter-system file transfers.
Mitigation strategies for CVE-2006-6915 should focus on immediate patching of affected IBM AIX systems with the appropriate security updates provided by IBM. Organizations should implement network monitoring to detect unusual connection patterns that may indicate exploitation attempts, particularly monitoring for rapid connection establishment and termination cycles. System administrators should consider implementing connection rate limiting and port allocation restrictions to prevent malicious users from exhausting available ports. The vulnerability aligns with CWE-400 which categorizes resource exhaustion issues, and represents a specific implementation weakness in network service handling that could be addressed through proper input validation and resource management. From an ATT&CK framework perspective, this vulnerability maps to techniques involving resource exhaustion and service disruption, potentially enabling broader attack chains that could lead to privilege escalation or system compromise if combined with other vulnerabilities. Organizations should also consider implementing network segmentation and access controls to limit the potential impact of authenticated users who might exploit this vulnerability, ensuring that only authorized personnel have access to FTP services and that appropriate auditing is maintained for all FTP activities.