CVE-2018-12909 in Webgrind
Summary
by MITRE
** DISPUTED ** Webgrind 1.5 relies on user input to display a file, which lets anyone view files from the local filesystem (that the webserver user has access to) via an index.php?op=fileviewer&file= URI. NOTE: the vendor indicates that the product is not intended for a "publicly accessible environment."
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Analysis
by VulDB Data Team • 08/05/2024
The vulnerability identified as CVE-2018-12909 affects Webgrind version 1.5, a web-based application designed for profiling php applications. This issue represents a critical directory traversal flaw that allows unauthorized users to access arbitrary files on the web server's filesystem through a simple URI parameter manipulation. The vulnerability stems from insufficient input validation within the application's file viewing functionality, specifically in the index.php script where the 'file' parameter is directly used to determine which file to display without proper sanitization or access control checks. This weakness creates a path traversal condition that can be exploited by attackers to view sensitive files such as configuration files, source code, or other system resources that the web server process has access to.
The technical exploitation of this vulnerability occurs through a straightforward GET request pattern where an attacker crafts a URI with the op=fileviewer parameter and a file parameter pointing to any accessible file path on the server. This flaw directly maps to CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks. The vulnerability allows for arbitrary file reading across the filesystem, potentially exposing sensitive data including database credentials, application configuration files, or even source code that could provide attackers with additional attack vectors. The impact is particularly severe because the web server process typically runs with elevated privileges and may have access to files that should normally be restricted from public access.
From an operational perspective, this vulnerability transforms a potentially contained application into a serious security risk when deployed in environments where the application might be accessible to unauthenticated users. The vendor's statement that the product is not intended for publicly accessible environments does not mitigate the risk when applications are improperly deployed or when the application is exposed through misconfigurations. The vulnerability can be exploited by any user who can access the web application, making it particularly dangerous in shared hosting environments or when applications are not properly secured. Attackers can leverage this flaw to extract sensitive information that could lead to further compromise of the system or network, potentially enabling privilege escalation or lateral movement within the infrastructure. This vulnerability directly aligns with ATT&CK technique T1213.002 which covers data from information repositories and can be used as a reconnaissance step to gather intelligence about the target environment.
The recommended mitigation strategies include implementing proper input validation and sanitization for all user-supplied parameters, particularly those used for file operations. Organizations should ensure that Webgrind is deployed in secure, restricted environments where only authorized personnel have access, and that proper authentication and authorization mechanisms are in place. The application should be configured to run in a dedicated, isolated environment with minimal privileges, and network segmentation should be implemented to prevent unauthorized access. Additionally, implementing proper access controls and restricting file access through proper path validation can prevent attackers from traversing directories and accessing unintended files. Regular security assessments and code reviews should be conducted to identify similar vulnerabilities in other applications, as this type of flaw is common in applications that handle file operations without proper security considerations. The vulnerability also underscores the importance of following secure coding practices and implementing proper input validation as outlined in OWASP Top 10 security guidelines.