CVE-2008-6948 in Collabtive
Summary
by MITRE
Unrestricted file upload vulnerability in Collabtive 0.4.8 allows remote authenticated users to execute arbitrary code by uploading a file with an executable extension and using a text/plain MIME type, then accessing it via a direct request to the file in files/, related to (1) the showproject action in managefile.php or (2) the Messages feature.
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Analysis
by VulDB Data Team • 11/10/2024
The CVE-2008-6948 vulnerability represents a critical unrestricted file upload flaw in Collabtive version 0.4.8 that enables authenticated remote attackers to execute arbitrary code on the target system. This vulnerability stems from inadequate input validation and sanitization mechanisms within the file upload functionality of the web application. The flaw specifically manifests when users upload files with executable extensions while employing a text/plain MIME type, creating a dangerous condition that bypasses typical security controls designed to prevent malicious file execution. The vulnerability is particularly concerning because it operates within a legitimate application feature set, making it more difficult to detect and prevent through standard security monitoring.
The technical implementation of this vulnerability involves two primary attack vectors within the Collabtive application architecture. The first vector relates to the showproject action in the managefile.php component where file handling logic fails to properly validate file extensions and MIME types against a whitelist of allowed formats. The second vector involves the Messages feature which similarly lacks proper file validation controls. Both pathways allow attackers to upload malicious files that can be executed directly through web requests to the files/ directory. This vulnerability directly maps to CWE-434, which describes the weakness of unrestricted upload of executable files, and demonstrates a classic case of insufficient input validation. The attack requires authentication, meaning that an attacker must first obtain valid credentials, but once achieved, the impact is severe as it allows for complete system compromise through code execution.
The operational impact of this vulnerability extends beyond simple code execution to encompass full system compromise and potential lateral movement within network environments. When an attacker successfully uploads a malicious file and accesses it through the direct file request mechanism, they can execute arbitrary commands on the vulnerable server with the privileges of the web application user. This creates a persistent backdoor capability that can be used for data exfiltration, system reconnaissance, and further attack propagation. The vulnerability's presence in a collaboration platform like Collabtive is particularly dangerous as these applications often contain sensitive business data and may have elevated privileges within corporate networks. The attack pattern aligns with ATT&CK technique T1190, which describes exploitation of vulnerabilities in web applications, and T1078, which covers valid accounts usage for persistence and privilege escalation.
Mitigation strategies for CVE-2008-6948 must address both the immediate vulnerability and implement broader security controls. The primary fix involves implementing strict file type validation that enforces whitelisting of allowed file extensions and MIME types, while also ensuring that uploaded files are stored outside the web root directory. Additional measures include implementing proper file name sanitization, adding content type verification beyond simple MIME type checking, and ensuring that uploaded files are not directly executable. Security headers should be implemented to prevent automatic execution of uploaded content, and access controls should be enforced to limit who can upload files. Regular security audits and input validation testing should be conducted to prevent similar vulnerabilities from emerging in future versions. Organizations should also implement network monitoring to detect unauthorized file upload activities and establish incident response procedures for rapid remediation when such vulnerabilities are discovered. The vulnerability serves as a reminder of the critical importance of secure file handling practices in web applications and the need for comprehensive input validation across all user-supplied data pathways.