CVE-2011-1975 in Windows
Summary
by MITRE
Untrusted search path vulnerability in the Data Access Tracing component in Windows Data Access Components (Windows DAC) 6.0 in Microsoft Windows 7 Gold and SP1 and Windows Server 2008 R2 and R2 SP1 allows local users to gain privileges via a Trojan horse DLL in the current working directory, as demonstrated by a directory that contains an Excel .xlsx file, aka "Data Access Components Insecure Library Loading Vulnerability."
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Analysis
by VulDB Data Team • 01/12/2025
The vulnerability identified as CVE-2011-1975 represents a critical untrusted search path issue within the Data Access Tracing component of Microsoft Windows Data Access Components version 6.0. This flaw exists in Windows 7 Gold and SP1 operating systems as well as Windows Server 2008 R2 and R2 SP1, creating a significant security risk for enterprise environments. The vulnerability stems from improper handling of dynamic library loading processes where the system searches for required DLL files in the current working directory before checking system directories, allowing malicious actors to place crafted DLL files in locations that will be loaded automatically. The specific attack vector demonstrated in the exploit involves placing a Trojan horse DLL in the same directory as an Excel .xlsx file, which triggers the vulnerable data access component during file processing operations. This vulnerability is classified under CWE-427 Uncontrolled Search Path Element, which specifically addresses situations where applications search for libraries in insecure locations, and aligns with ATT&CK technique T1068 for Local Privilege Escalation through DLL hijacking.
The technical exploitation of this vulnerability relies on the principle of insecure library loading where the Windows DAC component fails to properly validate the source of dynamically loaded libraries. When a user opens an Excel file or performs data access operations, the vulnerable component searches for required DLL files in the current working directory first, before consulting the system's standard library search paths. This allows a local attacker to place a malicious DLL with the same name as a legitimate system library in the directory containing the target Excel file. When the data access tracing component attempts to load the library, it loads the attacker-controlled DLL instead of the legitimate system version, enabling privilege escalation. The vulnerability is particularly dangerous because it requires minimal user interaction for exploitation, as simply opening an Excel file in a directory containing the malicious DLL can trigger the attack. This behavior violates the principle of least privilege and demonstrates how insecure library loading can be leveraged for privilege escalation attacks.
The operational impact of CVE-2011-1975 extends beyond simple local privilege escalation, as it provides attackers with the ability to execute arbitrary code with elevated privileges on affected systems. Once successfully exploited, the attacker can gain system-level access, potentially leading to complete system compromise, data exfiltration, or establishment of persistent backdoors. The vulnerability affects a wide range of Microsoft Windows operating systems, making it particularly concerning for enterprise environments where these systems are commonly deployed. Organizations with multiple users accessing shared directories or using applications that process external data files face heightened risk, as the attack can be initiated through seemingly benign file operations. The vulnerability also impacts the overall security posture of systems by enabling attackers to bypass standard security controls and escalate privileges without requiring additional attack vectors or complex exploitation techniques. This makes it an attractive target for threat actors seeking to establish persistent access or escalate their privileges within compromised environments.
Mitigation strategies for CVE-2011-1975 should focus on both immediate patching and operational security measures. Microsoft released security updates addressing this vulnerability through Windows Update, and organizations should prioritize applying these patches to all affected systems. In the interim, system administrators can implement several defensive measures including restricting write permissions to directories containing executable files, implementing application whitelisting policies to prevent unauthorized DLL loading, and conducting regular security audits of system directories. Network segmentation and privilege separation can help limit the impact if exploitation occurs, while monitoring for unusual DLL loading activities can provide early detection of potential attacks. Organizations should also consider implementing the principle of least privilege, ensuring that user accounts have minimal required permissions and that system services run with reduced privileges. Additionally, regular security awareness training can help users understand the risks associated with opening files from untrusted sources, as social engineering remains a common initial attack vector for exploiting such vulnerabilities. The vulnerability serves as a reminder of the critical importance of secure coding practices and proper library loading mechanisms in preventing privilege escalation attacks.