CVE-2018-18061 in Responsive FileManager
Summary
by MITRE
An issue was discovered in dialog.php in tecrail Responsive FileManager 9.8.1. Attackers can access the file manager interface that provides them with the ability to upload and delete files.
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Analysis
by VulDB Data Team • 04/01/2020
The vulnerability identified as CVE-2018-18061 represents a critical access control flaw within the tecrail Responsive FileManager version 9.8.1. This issue manifests in the dialog.php component which serves as the primary interface for file management operations. The flaw allows unauthenticated attackers to bypass legitimate authentication mechanisms and gain direct access to the file manager functionality. The vulnerability stems from insufficient input validation and authorization checks within the application's access control architecture, creating a pathway for malicious actors to exploit the system's file management capabilities without proper credentials.
The technical implementation of this vulnerability involves a failure in the application's session management and permission validation logic. When users attempt to access the dialog.php interface, the system does not properly verify whether the requesting entity possesses the necessary privileges to perform file operations. This weakness creates an unauthorized access vector that enables attackers to navigate directly to the file manager interface through predictable URL patterns or by exploiting the application's default configurations. The flaw operates at the application layer and affects the web server's ability to enforce proper access controls, making it particularly dangerous as it allows for both read and write operations on the target file system.
From an operational perspective, this vulnerability presents significant risks to organizations utilizing the affected file manager software. Attackers who successfully exploit this flaw can upload malicious files such as web shells, backdoors, or other harmful executables directly to the server filesystem. The ability to delete files further amplifies the potential damage as attackers can remove critical system files, corrupt data, or implement destructive operations. The impact extends beyond simple unauthorized access to include potential privilege escalation, data exfiltration, and system compromise. This vulnerability aligns with CWE-285 which addresses improper authorization issues, and represents a clear violation of the principle of least privilege in system security design.
The exploitation of this vulnerability follows patterns consistent with the attack techniques described in the MITRE ATT&CK framework under the T1078 credential access and T1059 execution techniques. Attackers typically begin by identifying the vulnerable endpoint and then attempt to access the dialog.php interface without authentication. Once access is gained, they can leverage the file upload functionality to deploy malicious payloads, potentially establishing persistent access to the compromised system. The vulnerability's impact is compounded by the fact that it affects the core file management functionality of the application, making it a high-value target for threat actors seeking to maintain long-term access to compromised systems.
Mitigation strategies for CVE-2018-18061 should focus on implementing proper access controls and authentication mechanisms throughout the application. Organizations should immediately apply the vendor-supplied patches or updates that address the authorization flaw in the dialog.php component. Network-level protections including web application firewalls and access control lists can provide additional defense in depth. The implementation of strong authentication protocols, session management controls, and regular security assessments can help prevent similar vulnerabilities from emerging in the future. Additionally, organizations should conduct thorough security reviews of all file management interfaces to ensure proper authorization checks are implemented across all application components. The remediation process should include disabling unnecessary file upload capabilities when not required for legitimate business functions, and implementing proper input validation and output encoding to prevent further exploitation attempts.