CVE-2019-17199 in webpagetest
Summary
by MITRE
www/getfile.php in WPO WebPageTest 19.04 on Windows allows Directory Traversal (for reading arbitrary files) because of an unanchored regular expression, as demonstrated by the a.jpg\.. substring.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 01/03/2024
The vulnerability identified as CVE-2019-17199 affects WPO WebPageTest version 19.04 on Windows systems and represents a critical directory traversal flaw in the www/getfile.php component. This security weakness stems from an improperly configured regular expression that fails to anchor the pattern matching, creating an exploitable condition that allows attackers to access arbitrary files on the target system. The specific exploitation technique involves appending the substring a.jpg\.. to file requests, which demonstrates how the unanchored regex fails to properly validate input parameters before processing file access requests.
The technical root cause of this vulnerability aligns with CWE-22, which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks. The unanchored regular expression in the getfile.php script fails to properly validate user-supplied input, allowing malicious actors to manipulate file path parameters and bypass intended access controls. This flaw specifically affects the file handling mechanism within the WebPageTest framework, where the application processes requests for various file types including images and other resources without adequate sanitization of the input parameters.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with the ability to read arbitrary files from the target system's file structure. This capability could potentially expose sensitive configuration files, database credentials, application source code, or other confidential data that may reside within the web server's directory structure. Attackers could leverage this vulnerability to gain unauthorized access to system files that should normally be restricted to authorized users only, potentially leading to further exploitation opportunities including privilege escalation or system compromise.
The attack vector for CVE-2019-17199 follows patterns consistent with the ATT&CK framework's privilege escalation and defense evasion techniques, particularly when considering how directory traversal vulnerabilities can be used to access system-level information. Security professionals should note that this vulnerability specifically targets the Windows implementation of WebPageTest, making it relevant for organizations running this particular software stack in their performance testing environments. The exploitation requires minimal technical sophistication and can be automated, making it particularly dangerous in environments where WebPageTest is deployed without proper network segmentation or access controls.
Mitigation strategies for this vulnerability should include immediate patching of the affected WebPageTest version to the latest available release that addresses the directory traversal issue. Organizations should also implement input validation measures that properly anchor regular expressions and sanitize all user-supplied parameters before processing file access requests. Network segmentation and access controls should be enforced to limit exposure of the vulnerable web application to untrusted networks, while monitoring systems should be configured to detect anomalous file access patterns that may indicate exploitation attempts. Additionally, regular security assessments should be conducted to identify and remediate similar vulnerabilities in other web applications within the organization's infrastructure, particularly those that handle user input for file operations.