CVE-2016-10733 in ProjectSend
Summary
by MITRE
ProjectSend (formerly cFTP) r582 allows directory traversal via file=../ in the process-zip-download.php query string.
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Analysis
by VulDB Data Team • 04/07/2020
ProjectSend represents a web-based file sharing platform that has historically been vulnerable to directory traversal attacks through improper input validation in its file processing components. The specific vulnerability identified as CVE-2016-10733 affects version r582 of ProjectSend, which is a critical security flaw that allows unauthorized users to access files outside of the intended directory structure. This vulnerability manifests through the process-zip-download.php script where the file parameter accepts directory traversal sequences, specifically the ../ notation that enables attackers to navigate upward through the file system hierarchy.
The technical exploitation of this vulnerability occurs when the application fails to properly sanitize or validate user-supplied input passed through the query string parameter. When an attacker crafts a malicious request containing the file=../ sequence, the application processes this input without adequate validation, allowing the traversal to occur. This flaw directly maps to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as directory traversal or path traversal. The vulnerability enables attackers to access sensitive files that may contain configuration details, user credentials, application source code, or other confidential data that should remain isolated from unauthorized access.
The operational impact of this directory traversal vulnerability extends beyond simple file access, as it can potentially lead to complete system compromise. An attacker could leverage this vulnerability to access critical system files, database configuration files, or application source code that might reveal additional attack vectors or sensitive information. The vulnerability affects the principle of least privilege by allowing unauthorized access to files that should be restricted to authorized users only. This weakness can be exploited in conjunction with other vulnerabilities to escalate privileges or gain deeper system access, making it particularly dangerous in environments where ProjectSend is deployed.
Security professionals should implement several mitigation strategies to address this vulnerability. The most effective approach involves implementing strict input validation and sanitization for all user-supplied parameters, particularly those related to file operations. The application should enforce a whitelist approach for file access, ensuring that only files within predetermined directories can be accessed through the download functionality. Additionally, proper file permission controls and the principle of least privilege should be enforced to minimize the impact of any potential exploitation. Organizations should also consider implementing web application firewalls that can detect and block suspicious traversal patterns, and regular security assessments should be conducted to identify similar vulnerabilities in other components of the application. This 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 it enables unauthorized access to system resources that could be leveraged for further exploitation.