CVE-2005-4855 in eZ publish
Summary
by MITRE
Unrestricted file upload vulnerability in eZ publish 3.5 before 3.5.5, 3.6 before 3.6.2, 3.7 before 3.7.0rc2, and 3.8 before 20050922 does not restrict Image datatype uploads to image content types, which allows remote authenticated users to upload certain types of files, as demonstrated by .js files, which may enable cross-site scripting (XSS) attacks or other attacks.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 07/31/2017
The CVE-2005-4855 vulnerability represents a critical unrestricted file upload flaw in eZ publish content management systems across multiple versions including 3.5 before 3.5.5, 3.6 before 3.6.2, 3.7 before 3.7.0rc2, and 3.8 before 20050922. This vulnerability specifically affects the Image datatype functionality within the system's content management interface, where authenticated users can bypass intended content type restrictions. The flaw stems from insufficient validation mechanisms that fail to properly verify file types during the upload process, allowing malicious actors to upload files with extensions that should be restricted to image formats only. This vulnerability operates under the broader category of CWE-434, which encompasses unrestricted upload of file with dangerous type, and aligns with ATT&CK technique T1190 for exploiting vulnerabilities in web applications. The security implications extend beyond simple file type validation as the vulnerability permits the upload of executable scripts and other malicious content that can be leveraged for various attack vectors.
The technical execution of this vulnerability relies on the system's failure to properly validate file content and extensions within the Image datatype upload mechanism. When authenticated users attempt to upload files through the content management interface, the system accepts files regardless of their actual content type, permitting uploads of JavaScript files and other potentially harmful content. This occurs because the validation logic only checks file extensions rather than examining the actual file structure and content, a common weakness in web application security implementations. The vulnerability specifically targets the Image datatype handling, which should logically restrict uploads to standard image formats such as jpg, png, gif, and bmp, but instead accepts any file type that matches the extension requirements. This flaw creates a pathway for attackers to bypass intended security controls and execute malicious code within the context of the web application.
The operational impact of CVE-2005-4855 is severe and multifaceted, as it enables remote authenticated users to potentially execute cross-site scripting attacks and other malicious activities. The ability to upload .js files and similar executable content provides attackers with opportunities to inject malicious scripts that can compromise user sessions, steal sensitive information, or manipulate content within the web application. This vulnerability can be exploited to perform session hijacking, defacement of web content, or serve as a launching point for more sophisticated attacks such as privilege escalation or lateral movement within the network. The vulnerability's impact extends to both the availability and integrity of the web application, as malicious uploads can disrupt normal operations while simultaneously compromising the system's security posture. Attackers can leverage this weakness to establish persistent access to the system or to create backdoors that can be used for ongoing exploitation.
Mitigation strategies for CVE-2005-4855 require immediate implementation of comprehensive file validation mechanisms and access controls. Organizations should implement strict file type validation that examines both file extensions and actual content signatures rather than relying solely on extension checks. The system should enforce content-type validation and implement proper file handling procedures that verify file integrity before storage. Additionally, administrators should restrict upload privileges to only essential users and implement proper access controls to limit the scope of potential exploitation. The recommended approach includes implementing a whitelist of allowed file types, conducting thorough content analysis of uploaded files, and ensuring that uploaded files are stored in a secure location separate from the web root directory. Organizations should also consider implementing web application firewalls and intrusion detection systems to monitor for suspicious upload activities and provide additional layers of protection against exploitation attempts. Regular security audits and vulnerability assessments should be conducted to identify and remediate similar weaknesses in other web applications and content management systems.