CVE-2017-16166 in byucslabsix
Summary
by MITRE
byucslabsix is an http server. byucslabsix is vulnerable to a directory traversal issue, giving an attacker access to the filesystem by placing "../" in the url.
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Analysis
by VulDB Data Team • 02/16/2020
The CVE-2017-16166 vulnerability affects byucslabsix, an HTTP server implementation that suffers from a critical directory traversal flaw. This vulnerability allows attackers to access arbitrary files on the underlying filesystem by manipulating URL parameters through the use of directory traversal sequences such as "../". The flaw represents a fundamental security weakness in the server's input validation and file access controls, enabling unauthorized information disclosure and potential system compromise.
This vulnerability maps directly to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks. The issue occurs when user-supplied input is not properly validated or sanitized before being used to access files or directories on the server. In the context of byucslabsix, the HTTP server fails to adequately sanitize URL paths, allowing malicious actors to navigate outside the intended document root directory and access sensitive system files, configuration data, or other restricted resources.
The operational impact of CVE-2017-16166 is significant and multifaceted. Attackers can potentially access critical system files including password files, configuration databases, application source code, and other sensitive data stored on the server. This vulnerability can be exploited through simple URL manipulation, making it particularly dangerous as it requires minimal technical expertise to execute. The attack vector aligns with techniques described in the MITRE ATT&CK framework under T1083 (File and Directory Discovery) and T1566 (Phishing for Information) where adversaries leverage path traversal to gather intelligence about the target system. Depending on the server configuration and file permissions, exploitation could lead to complete system compromise through access to system binaries, databases, or administrative credentials.
Mitigation strategies for CVE-2017-16166 should include immediate implementation of input validation and sanitization measures. The server should be configured to reject or filter out directory traversal sequences such as "../", "..\", and similar patterns from URL parameters. Proper path validation should ensure that all file access operations occur within designated directories and that user input is normalized and validated before processing. Security patches should be applied to update the byucslabsix server to versions that address this vulnerability. Additionally, implementing proper access controls and least privilege principles can limit the damage if exploitation occurs. Network segmentation and monitoring should be employed to detect and prevent unauthorized access attempts, while regular security audits can help identify similar vulnerabilities in other server components or applications within the infrastructure. Organizations should also consider implementing web application firewalls and security monitoring solutions to detect and block malicious path traversal attempts in real-time.