CVE-2018-15698 in Data Master
Summary
by MITRE
ASUSTOR Data Master 3.1.5 and below allows authenticated remote non-administrative users to read any file on the file system when providing the full path to loginimage.cgi.
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Analysis
by VulDB Data Team • 03/18/2020
The vulnerability identified as CVE-2018-15698 affects ASUSTOR Data Master versions 3.1.5 and earlier, presenting a critical security flaw that enables authenticated but non-administrative users to access arbitrary files on the system. This issue resides within the loginimage.cgi component of the software, which fails to properly validate user input when processing file paths. The vulnerability stems from inadequate access controls and path traversal mechanisms that allow malicious users to bypass normal file system restrictions through crafted requests.
The technical implementation of this flaw involves the loginimage.cgi script failing to sanitize user-supplied path parameters, creating a directory traversal condition that permits attackers to navigate beyond the intended file system boundaries. When an authenticated user submits a request containing a specially crafted file path to the loginimage.cgi endpoint, the application processes this input without proper validation, resulting in unauthorized file access. This vulnerability operates under the Common Weakness Enumeration classification of CWE-22, which specifically addresses improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks.
The operational impact of this vulnerability is significant as it allows attackers with only basic user credentials to escalate their privileges and access sensitive system files that should normally be restricted to administrative users. This includes potentially accessing configuration files, user credentials, system logs, and other confidential data that could provide further attack vectors or compromise the entire system. The vulnerability affects the confidentiality and integrity aspects of the CIA triad, as unauthorized file access can lead to data exfiltration and potential system compromise.
The attack surface is particularly concerning because it requires only authentication, which is often easier to obtain than administrative privileges. Attackers could potentially exploit this vulnerability by first gaining access to a legitimate user account through various means such as credential theft, social engineering, or weak authentication mechanisms. Once authenticated, they could leverage this path traversal flaw to access critical system information that could aid in further exploitation. According to the MITRE ATT&CK framework, this vulnerability aligns with techniques involving privilege escalation and credential access, as it allows for unauthorized access to system resources that should be protected.
Mitigation strategies for this vulnerability include immediate patching of the ASUSTOR Data Master software to version 3.1.6 or later, which addresses the path traversal issue through proper input validation and access control mechanisms. Organizations should also implement network segmentation to limit access to administrative interfaces and enforce strong authentication controls including multi-factor authentication. Additionally, regular security audits and penetration testing should be conducted to identify similar vulnerabilities in other networked systems. System administrators should monitor for unusual file access patterns and implement proper logging mechanisms to detect potential exploitation attempts. The vulnerability demonstrates the importance of proper input validation and access control implementation, reinforcing industry best practices outlined in standards such as NIST SP 800-53 and ISO 27001 for secure system design and implementation.