CVE-2008-6518 in VidiScript
Summary
by MITRE
Unrestricted file upload vulnerability in the profile feature in VidiScript allows registered remote authenticated users to execute arbitrary code by uploading a PHP file as an Avatar, then accessing the avatar via a direct request.
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Analysis
by VulDB Data Team • 11/03/2024
The vulnerability identified as CVE-2008-6518 represents a critical security flaw within the VidiScript platform's profile management functionality. This unrestricted file upload vulnerability specifically targets the avatar upload feature, which is typically designed to allow users to personalize their profiles with images. The flaw exists in the server-side validation mechanisms that fail to properly restrict file types during the upload process, creating an exploitable condition that can be leveraged by authenticated attackers.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the file upload handler. When registered users attempt to upload avatar files, the system does not properly verify the file extensions or content types, allowing malicious actors to bypass security checks by uploading PHP files with deceptive names or extensions. The vulnerability operates through a simple yet effective attack vector where an authenticated user uploads a malicious PHP script disguised as an image file, then accesses the uploaded file directly through a web request to execute arbitrary code on the server.
From an operational perspective, this vulnerability poses significant risks to system integrity and data security. Successful exploitation enables attackers to execute arbitrary code with the privileges of the web application, potentially leading to complete system compromise, data theft, or further lateral movement within the network. The authenticated nature of the attack means that the attacker must first obtain legitimate credentials, but this requirement does not significantly mitigate the risk since legitimate users with access can be compromised through various means such as credential theft, social engineering, or session hijacking techniques.
The impact of this vulnerability aligns with CWE-434, which describes the weakness of unrestricted upload of file with dangerous type, and can be mapped to ATT&CK technique T1190 for exploiting vulnerabilities in web applications. The attack chain typically involves reconnaissance to identify the vulnerable profile feature, authentication using valid credentials, file upload with malicious PHP content, and execution of commands through direct web requests to the uploaded file. Organizations running VidiScript systems are particularly vulnerable since the flaw affects the core user management functionality that is essential for platform operations.
Mitigation strategies for CVE-2008-6518 require immediate implementation of comprehensive file validation measures including strict content type checking, filename extension filtering, and proper file handling procedures. Organizations should implement whitelisting approaches that only allow specific, safe file extensions and MIME types while rejecting all other uploads. Additionally, uploaded files should be stored outside the web root directory, and proper access controls should be implemented to prevent direct execution of uploaded content. Regular security updates and patch management processes should be enforced to address similar vulnerabilities in web applications, while comprehensive monitoring and logging of file upload activities can help detect and respond to potential exploitation attempts.