CVE-2012-4206 in Firefox
Summary
by MITRE
Untrusted search path vulnerability in the installer in Mozilla Firefox before 17.0 and Firefox ESR 10.x before 10.0.11 on Windows allows local users to gain privileges via a Trojan horse DLL in the default downloads directory.
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Analysis
by VulDB Data Team • 10/22/2024
The vulnerability identified as CVE-2012-4206 represents a critical untrusted search path issue within the Windows installer component of Mozilla Firefox versions prior to 17.0 and Firefox ESR 10.x prior to 10.0.11. This flaw resides in the installer's handling of dynamic link library loading processes on Windows operating systems, creating a privilege escalation vector that adversaries can exploit through carefully crafted malicious files. The vulnerability specifically targets the default downloads directory where Firefox stores downloaded files, making it an attractive target for attackers seeking to execute arbitrary code with elevated privileges.
The technical mechanism behind this vulnerability stems from the installer's insecure search path implementation, which fails to properly validate or sanitize the paths from which dynamic libraries are loaded. When Firefox installs or updates components on Windows systems, it searches for required DLL files in a predetermined sequence that includes the default downloads directory. This behavior creates an opportunity for local attackers to place malicious DLL files in the downloads folder, which the installer will then load and execute without proper validation. The vulnerability is categorized under CWE-426 as an "Untrusted Search Path" and aligns with ATT&CK technique T1068 which covers "Exploitation for Privilege Escalation."
The operational impact of this vulnerability is significant, as it allows local users to escalate their privileges from standard user level to administrator level. Attackers can leverage this weakness by placing a malicious DLL file with the same name as a legitimate Firefox component in the downloads directory, effectively hijacking the installation process. This privilege escalation capability enables adversaries to install malware, modify system files, or establish persistent access to the compromised system. The vulnerability is particularly dangerous because it requires no special privileges to exploit, making it accessible to any local user who can write to the downloads directory.
Mitigation strategies for CVE-2012-4206 involve immediate patching of affected Firefox versions to the latest stable releases, which address the untrusted search path issue through improved DLL loading mechanisms. System administrators should also implement proper access controls on the downloads directory to restrict write permissions to authorized users only, and consider implementing application whitelisting policies to prevent unauthorized DLL execution. The vulnerability demonstrates the importance of secure coding practices in installer components and highlights the need for proper input validation and secure library loading mechanisms as outlined in the OWASP Secure Coding Practices. Organizations should also monitor for any indicators of compromise related to malicious DLL files in user downloads directories and maintain updated security tooling to detect potential exploitation attempts.