CVE-2012-2657 in unixODBC
Summary
by MITRE
** DISPUTED ** Buffer overflow in the SQLDriverConnect function in unixODBC 2.0.10, 2.3.1, and earlier allows local users to cause a denial of service (crash) via a long string in the FILEDSN option. NOTE: this issue might not be a vulnerability, since the ability to set this option typically implies that the attacker already has legitimate access to cause a DoS or execute code, and therefore the issue would not cross privilege boundaries. There may be limited attack scenarios if isql command-line options are exposed to an attacker, although it seems likely that other, more serious issues would also be exposed, and this issue might not cross privilege boundaries in that context.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 03/04/2025
The vulnerability described in CVE-2012-2657 represents a buffer overflow condition within the SQLDriverConnect function of unixODBC versions 2.0.10, 2.3.1, and earlier. This flaw specifically manifests when processing the FILEDSN option parameter, where an attacker can provide an excessively long string that exceeds the allocated buffer space. The unixODBC library serves as a critical middleware component for database connectivity on unix-like systems, facilitating communication between applications and database drivers through the open database connectivity standard. The buffer overflow occurs during the processing of connection strings where the FILEDSN parameter is used to specify the location of a data source name file, creating a scenario where memory corruption can occur when the input string length surpasses the predefined buffer boundaries.
The technical implementation of this vulnerability stems from inadequate input validation and bounds checking within the SQLDriverConnect function. When the FILEDSN option is processed, the implementation fails to properly verify the length of the provided string before copying it into a fixed-size buffer. This classic buffer overflow condition can lead to memory corruption that manifests as application crashes, segmentation faults, or potentially more severe consequences depending on the execution environment. The vulnerability operates at the system level where the unixODBC library handles database connection requests, making it a potential vector for denial of service attacks against applications that rely on this middleware component for database access.
From an operational impact perspective, this vulnerability creates significant security implications for systems that depend on unixODBC for database connectivity. While the vulnerability description acknowledges that it may not constitute a true privilege escalation issue since FILEDSN parameter access typically requires existing legitimate access to the system, the potential for denial of service remains a serious concern. The impact extends beyond simple service disruption as database connectivity failures can cascade through entire application ecosystems, affecting business operations and potentially leading to data access interruptions. The vulnerability becomes particularly concerning in environments where database applications are critical to business processes or where automated systems rely on consistent database connectivity for their operations.
The vulnerability may be classified under CWE-121 as a stack-based buffer overflow or CWE-122 as a heap-based buffer overflow depending on the specific implementation details of the buffer allocation. From an attack framework perspective, this issue aligns with ATT&CK technique T1499.004 for network denial of service and potentially T1566.001 for malicious file execution if the buffer overflow leads to code execution. The security implications extend beyond simple DoS as the vulnerability may expose underlying system instability that could be leveraged in combination with other weaknesses. Organizations should consider this vulnerability in the context of their overall security posture, particularly in environments where database connectivity is essential for business operations.
Mitigation strategies for this vulnerability should focus on immediate remediation through software updates to newer versions of unixODBC that have addressed the buffer overflow issue. System administrators should implement proper input validation and length checking mechanisms within applications that utilize unixODBC to reduce the risk of exploitation. Additionally, access controls should be enforced to limit who can provide input to database connection functions, particularly where the FILEDSN parameter is involved. The vulnerability highlights the importance of proper memory management and input validation in middleware components, emphasizing that even seemingly benign parameters can create critical security risks. Organizations should conduct thorough vulnerability assessments to identify systems running affected unixODBC versions and implement comprehensive monitoring to detect potential exploitation attempts.