CVE-2005-4744 in FreeRADIUS
Summary
by MITRE
Off-by-one error in the sql_error function in sql_unixodbc.c in FreeRADIUS 1.0.2.5-5, and possibly other versions including 1.0.4, might allow remote attackers to cause a denial of service (crash) and possibly execute arbitrary code by causing the external database query to fail. NOTE: this single issue is part of a larger-scale disclosure, originally by SUSE, which reported multiple issues that were disputed by FreeRADIUS. Disputed issues included file descriptor leaks, memory disclosure, LDAP injection, and other issues. Without additional information, the most recent FreeRADIUS report is being regarded as the authoritative source for this CVE identifier.
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Analysis
by VulDB Data Team • 07/04/2019
The vulnerability identified as CVE-2005-4744 represents a critical off-by-one error within the sql_error function of the sql_unixodbc.c file in FreeRADIUS versions 1.0.2.5-5 and potentially 1.0.4. This flaw exists within the database connectivity layer of the FreeRADIUS authentication server, which serves as a central component for network access control and user authentication in various enterprise environments. The issue manifests when external database queries fail, creating a condition where memory boundaries are improperly handled, leading to unpredictable behavior that can compromise system stability and security.
The technical implementation of this vulnerability stems from improper buffer management in the sql_error function that processes database query failures. When a database connection fails or returns an error, the function attempts to handle the error condition but due to the off-by-one error, it accesses memory locations beyond the allocated buffer boundaries. This memory corruption can result in stack smashing or heap corruption patterns that typically lead to application crashes or in more sophisticated exploitation scenarios, potential code execution. The vulnerability specifically targets the Unix ODBC database interface implementation, making it particularly relevant for systems utilizing ODBC connections for database authentication.
The operational impact of this vulnerability extends beyond simple denial of service conditions, as it presents potential for remote code execution in certain circumstances. Attackers who can trigger database query failures through network-based interactions with the FreeRADIUS server could potentially cause the service to crash or in more advanced exploitation scenarios, gain arbitrary code execution privileges. This makes the vulnerability particularly dangerous in network infrastructure environments where FreeRADIUS servers handle authentication requests from multiple clients and network access points. The vulnerability affects the core authentication functionality, potentially compromising network security by allowing unauthorized access to systems that rely on FreeRADIUS for authentication.
The broader context of this vulnerability reveals a pattern of security issues within FreeRADIUS that were initially reported by SUSE but later disputed by the FreeRADIUS project team. This dispute highlights the complexity of vulnerability assessment and the challenges in determining the true scope and impact of security flaws in open source software. The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and could potentially map to ATT&CK techniques related to privilege escalation and denial of service. Organizations using FreeRADIUS in production environments should consider this vulnerability as part of a larger security posture assessment, particularly in environments where database authentication is critical to network security.
Mitigation strategies for this vulnerability should prioritize immediate patching of affected FreeRADIUS installations to the latest stable versions that contain the necessary code fixes for the buffer handling error. System administrators should also implement network segmentation and access controls to limit exposure of FreeRADIUS servers to untrusted networks, while monitoring for unusual authentication failures that might indicate exploitation attempts. Additionally, implementing proper database connection monitoring and error handling can help detect and prevent exploitation attempts, though the most effective solution remains applying the official security patches provided by the FreeRADIUS development team. Organizations should also consider implementing intrusion detection systems that can identify patterns consistent with this type of buffer overflow exploitation attempt.