CVE-2003-0491 in Tutorials
Summary
by MITRE
The Tutorials 2.0 module in XOOPS and E-XOOPS allows remote attackers to execute arbitrary code by uploading a PHP file without a MIME image type, then directly accessing the uploaded file.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 06/14/2018
The vulnerability identified as CVE-2003-0491 represents a critical security flaw in the Tutorials 2.0 module of XOOPS and E-XOOPS content management systems. This issue stems from inadequate input validation and file type verification mechanisms within the file upload functionality, creating a pathway for remote attackers to compromise affected systems. The vulnerability specifically targets the module's handling of file uploads where PHP files can be uploaded without proper MIME type checking, allowing malicious actors to bypass security controls designed to prevent execution of potentially harmful code.
The technical implementation of this vulnerability exploits the lack of proper file type validation in the upload process. When users upload files through the Tutorials 2.0 module, the system fails to properly verify the MIME type of uploaded files, permitting PHP scripts to be uploaded alongside legitimate image files. This occurs because the application relies on file extension checks rather than comprehensive MIME type verification, a common security weakness that has been documented in various security frameworks including CWE-434. The absence of robust file validation allows attackers to upload malicious PHP files with extensions that mimic legitimate image types, such as .jpg or .png, while maintaining the executable PHP code within the file content.
The operational impact of this vulnerability extends beyond simple code execution, as it provides attackers with a persistent means of gaining unauthorized access to affected systems. Once a malicious PHP file is successfully uploaded and accessed directly, attackers can execute arbitrary commands on the web server, potentially leading to complete system compromise. This vulnerability aligns with ATT&CK technique T1190, which describes the exploitation of vulnerabilities to gain initial access, and T1059, which covers the execution of commands through various methods including web shells. The remote nature of this attack means that exploitation can occur without requiring physical access to the system, making it particularly dangerous for web applications that are publicly accessible.
The security implications of CVE-2003-0491 demonstrate the critical importance of proper input validation and file handling practices in web applications. Organizations running XOOPS or E-XOOPS systems with the affected Tutorials 2.0 module face significant risk of unauthorized code execution, data theft, and potential system compromise. The vulnerability highlights the need for comprehensive security controls including proper MIME type verification, file extension filtering, and content validation. Additionally, this flaw underscores the necessity of implementing defense-in-depth strategies such as web application firewalls, regular security audits, and proper access controls to prevent unauthorized file uploads. The vulnerability also emphasizes the importance of keeping web applications updated and patched, as this issue was resolved through proper input validation and file type checking mechanisms that should be implemented in all file upload functionalities. Organizations should implement strict file upload validation policies that reject executable files regardless of their extensions, and ensure that uploaded files are stored outside the web root directory to prevent direct execution.