CVE-2018-15535 in Filemanager
Summary
by MITRE
/filemanager/ajax_calls.php in tecrail Responsive FileManager before 9.13.4 uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize get_file sequences such as ".." that can resolve to a location that is outside of that directory, aka Directory Traversal.
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Analysis
by VulDB Data Team • 08/03/2025
This vulnerability exists in the tecrail Responsive FileManager version 9.13.3 and earlier, where the filemanager/ajax_calls.php script fails to properly sanitize user input when constructing file paths for operations. The flaw allows attackers to manipulate file system access through directory traversal techniques by exploiting improper input validation of file paths. When external input is used to build pathnames for file operations, the application does not adequately neutralize special sequences such as ".." that would normally be filtered to prevent access outside of the intended restricted directory. This vulnerability falls under the CWE-22 category for Improper Limitation of a Pathname to a Restricted Directory, commonly known as Path Traversal or Directory Traversal. The issue represents a critical security flaw that can be exploited to access arbitrary files on the server, potentially leading to unauthorized data access, system compromise, or privilege escalation.
The operational impact of this vulnerability is severe as it allows an attacker to navigate outside the intended file management directory and access files that should remain restricted. An attacker could potentially read sensitive configuration files, database credentials, application source code, or other confidential data stored on the server. The vulnerability can be exploited through various attack vectors including direct manipulation of parameters passed to the ajax_calls.php endpoint, making it particularly dangerous for web applications that expose file management functionality. The flaw demonstrates poor input validation practices and inadequate path sanitization, which are fundamental security requirements for any file system interaction. This vulnerability can be categorized under ATT&CK technique T1083 (File and Directory Discovery) and T1566 (Phishing with Malicious Attachments) when leveraged in broader attack chains.
The technical exploitation of this vulnerability requires understanding that the application accepts user-supplied input without proper validation of path components. When the application constructs file paths using external input containing sequences like "../", it fails to normalize or validate these components against a whitelist of allowed characters or patterns. This allows attackers to craft malicious requests that can traverse directories and access files outside the intended scope. The vulnerability is particularly concerning because it affects a file manager component that is often exposed to end users, making it accessible through normal web browsing activities. Organizations should implement proper input validation, use secure path construction techniques, and enforce strict access controls to prevent such directory traversal attacks. The recommended mitigation includes updating to tecrail Responsive FileManager version 9.13.4 or later, implementing proper input sanitization, and applying restrictive file access controls to limit the impact of such vulnerabilities.