CVE-2017-16173 in utahcityfinder
Summary
by MITRE
utahcityfinder constructs lists of Utah cities with a certiain prefix. utahcityfinder 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 vulnerability identified as CVE-2017-16173 affects the utahcityfinder application which is designed to generate lists of Utah cities based on specific prefixes. This application appears to be a web-based service that processes user input to retrieve and display geographic information. The core issue lies in the application's improper handling of user-supplied input parameters, specifically within the URL processing mechanism. When users provide search parameters through the web interface, the application fails to adequately validate or sanitize the input before using it in file system operations.
The technical flaw manifests as a directory traversal vulnerability that allows attackers to manipulate the application's behavior by injecting ../ sequences into the URL parameters. This type of vulnerability is classified as CWE-22 - Improper Limitation of a Pathname to a Restricted Directory, which represents a fundamental weakness in input validation and path handling. The vulnerability occurs because the application directly incorporates user-provided path components into file system operations without proper sanitization or validation. When ../ sequences are included in the URL, they instruct the system to navigate up one directory level in the file system hierarchy, potentially allowing access to sensitive files outside the intended application directory.
The operational impact of this vulnerability is significant as it provides attackers with unauthorized access to the underlying file system. An attacker could potentially access configuration files, database credentials, application source code, or other sensitive system files that should remain protected. This vulnerability enables a wide range of malicious activities including data exfiltration, system reconnaissance, and potentially full system compromise depending on the application's permissions and the files accessible through the traversal. The attack vector is particularly concerning because it requires minimal technical expertise to exploit, making it attractive to both automated attacks and less sophisticated threat actors. This vulnerability directly maps to ATT&CK technique T1083 - File and Directory Discovery, as it enables attackers to enumerate and access files on the target system.
The mitigation strategies for this vulnerability involve implementing proper input validation and sanitization mechanisms. The application should reject or properly encode any input containing directory traversal sequences such as ../ or ..\ to prevent their use in file system operations. Implementing a whitelist approach for valid input parameters and using secure coding practices such as path normalization and validation can effectively prevent this class of vulnerability. Additionally, the application should operate with minimal required privileges and implement proper access controls to limit the damage even if traversal attacks succeed. Organizations should also consider implementing web application firewalls and input validation rules that can detect and block such malicious patterns at the network level. Regular security testing including vulnerability scanning and penetration testing should be conducted to identify similar issues in other applications and ensure that proper security controls are in place. The vulnerability demonstrates the critical importance of validating all user input and implementing proper security controls in web applications to prevent unauthorized access to system resources.