CVE-2017-6535 in webpagetest
Summary
by MITRE
Multiple Cross-Site Scripting (XSS) issues were discovered in webpagetest 3.0. The vulnerabilities exist due to insufficient filtration of user-supplied data (benchmark, url) passed to the webpagetest-master/www/benchmarks/trendurl.php URL. An attacker could execute arbitrary HTML and script code in a browser in the context of the vulnerable website.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 09/05/2020
The vulnerability identified as CVE-2017-6535 represents a critical cross-site scripting flaw in webpagetest version 3.0 that exposes the application to persistent security risks. This vulnerability specifically affects the webpagetest-master/www/benchmarks/trendurl.php endpoint where user-supplied data containing benchmark and url parameters is inadequately sanitized before being processed and rendered within the web interface. The flaw stems from the application's failure to implement proper input validation and output encoding mechanisms, creating an environment where malicious actors can inject harmful scripts that execute within the context of legitimate user sessions. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting issues and aligns with ATT&CK technique T1059.001 for command and scripting interpreter execution.
The technical implementation of this vulnerability allows attackers to manipulate the benchmark and url parameters through crafted input that bypasses the application's security controls. When the web application processes these unfiltered parameters, it directly incorporates them into the HTML output without proper sanitization or encoding, enabling malicious script execution in the victim's browser. The impact extends beyond simple script injection as it provides attackers with the ability to perform session hijacking, deface web pages, steal cookies, or redirect users to malicious sites. The vulnerability is particularly dangerous because it operates at the presentation layer where user input directly influences the rendered content, making it a prime target for exploitation in real-world scenarios.
From an operational perspective, this vulnerability creates significant risk for organizations using webpagetest for performance monitoring and benchmarking activities. The attack surface is broad as any user who can submit data through the trendurl.php endpoint can potentially exploit this flaw. The vulnerability enables persistent threats where attackers can establish backdoors or maintain access to the compromised system through injected scripts. Organizations may experience reputational damage, data breaches, and potential regulatory violations if this vulnerability is exploited against their web applications. The flaw also demonstrates poor security hygiene in input handling practices that could indicate broader security weaknesses within the application architecture.
Mitigation strategies for CVE-2017-6535 should prioritize immediate patching of the webpagetest application to the latest secure version that addresses the input validation issues. Organizations should implement comprehensive input sanitization measures including parameter validation, output encoding, and the use of Content Security Policy headers to limit script execution capabilities. The application should enforce strict validation of all user-supplied data and implement proper escaping mechanisms before rendering content. Security teams should also consider implementing web application firewalls to detect and block malicious input patterns, while conducting regular security assessments to identify similar vulnerabilities in other components. Additionally, proper security training for developers should emphasize secure coding practices and the importance of input validation to prevent such vulnerabilities from occurring in future releases.