CVE-2009-4512 in Oscailt
Summary
by MITRE
Directory traversal vulnerability in index.php in Oscailt 3.3, when Use Friendly URL s is disabled, allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the obj_id parameter.
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Analysis
by VulDB Data Team • 07/28/2025
The vulnerability identified as CVE-2009-4512 represents a critical directory traversal flaw within the Oscailt content management system version 3.3. This security weakness specifically manifests in the index.php script when the Friendly URLs feature is disabled, creating an exploitable condition that enables remote attackers to gain unauthorized access to local file systems. The vulnerability stems from insufficient input validation and sanitization of user-supplied parameters, particularly the obj_id parameter that controls object identification within the application's routing mechanism.
The technical implementation of this flaw occurs through the manipulation of the obj_id parameter to include directory traversal sequences such as .. (dot dot) characters. When the Friendly URLs feature is disabled, the application fails to properly sanitize or validate the incoming obj_id parameter before using it to construct file paths for inclusion and execution. This allows attackers to navigate outside the intended directory structure and access arbitrary local files on the server. The vulnerability operates at the application layer, specifically targeting the file inclusion mechanism that processes user input to determine which content files should be loaded and executed.
The operational impact of CVE-2009-4512 extends beyond simple information disclosure to encompass full system compromise potential. Attackers can leverage this vulnerability to execute arbitrary code on the target server, potentially gaining complete control over the affected system. The remote nature of the exploit means that attackers do not require physical access or local network privileges to exploit the vulnerability. This makes the flaw particularly dangerous as it can be exploited from anywhere on the internet, potentially leading to data breaches, service disruption, and unauthorized access to sensitive information stored on the compromised server. The vulnerability aligns with CWE-22, which classifies directory traversal attacks as a common weakness in input validation and access control mechanisms.
Mitigation strategies for this vulnerability should focus on immediate patching of the Oscailt application to version 3.4 or later, where the directory traversal issue has been addressed through proper input validation and sanitization. Additionally, administrators should implement proper parameter validation techniques that reject or sanitize any input containing directory traversal sequences before processing. Network-level protections such as web application firewalls can provide additional defense in depth by monitoring for suspicious parameter patterns. The vulnerability demonstrates the critical importance of input validation in preventing path traversal attacks and aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter, as successful exploitation could enable attackers to execute arbitrary commands on the compromised system through the file inclusion mechanism. Organizations should also consider implementing principle of least privilege access controls and regular security assessments to identify similar vulnerabilities in their application environments.