CVE-2020-5744 in TCExam
Summary
by MITRE
Relative Path Traversal in TCExam 14.2.2 allows a remote, authenticated attacker to read the contents of arbitrary files on disk.
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Analysis
by VulDB Data Team • 05/08/2020
The vulnerability identified as CVE-2020-5744 represents a critical relative path traversal flaw within TCExam version 14.2.2, a widely used web-based examination system. This security weakness enables authenticated attackers to exploit insufficient input validation mechanisms in the application's file handling processes, potentially allowing them to access sensitive files beyond the intended directory structure. The vulnerability specifically affects the application's ability to properly sanitize user-supplied input when processing file paths, creating an opportunity for malicious actors to navigate the file system and retrieve confidential data.
The technical implementation of this vulnerability stems from inadequate validation of file path parameters within the TCExam application's backend processing logic. When authenticated users submit requests containing specially crafted relative paths, the system fails to properly sanitize or validate these inputs before using them in file operations. This allows attackers to manipulate the file access routines through directory traversal sequences such as ../ or ..\, effectively bypassing the intended access controls and gaining unauthorized access to files that should remain protected. The flaw resides in the application's failure to implement proper input validation and path sanitization mechanisms, which are fundamental security controls recommended by the OWASP Top Ten and CWE-23 (Relative Path Traversal) classification.
The operational impact of CVE-2020-5744 extends beyond simple unauthorized file access, as it can potentially expose sensitive examination data, configuration files, database credentials, and other confidential information stored on the server. An authenticated attacker with minimal privileges can leverage this vulnerability to escalate their access and potentially compromise the entire examination system. The vulnerability affects the confidentiality and integrity aspects of the CIA triad, as it allows for unauthorized data disclosure and potential modification of system files. This type of vulnerability aligns with ATT&CK technique T1083 (File and Directory Discovery) and can contribute to broader attack chains leading to system compromise and data exfiltration. Organizations using TCExam 14.2.2 may face regulatory compliance issues and potential legal consequences if examination data breaches occur due to this vulnerability.
Mitigation strategies for CVE-2020-5744 should prioritize immediate application updates to the latest patched versions of TCExam, as the vendor has likely addressed this specific vulnerability in newer releases. Organizations should implement comprehensive input validation mechanisms that strictly filter and sanitize all user-supplied path parameters before processing, ensuring that relative path traversal sequences are rejected or properly normalized. Network segmentation and access control measures should be enforced to limit the privileges of authenticated users and reduce the potential impact of successful exploitation. Regular security audits and penetration testing should be conducted to identify similar vulnerabilities in other applications within the organization's infrastructure. Additionally, implementing proper logging and monitoring of file access patterns can help detect anomalous behavior indicative of exploitation attempts, while adherence to secure coding practices and regular security training for developers can prevent similar issues in future application development cycles.