CVE-2017-15429 in Chrome
Summary
by MITRE
Inappropriate implementation in V8 WebAssembly JS bindings in Google Chrome prior to 63.0.3239.108 allowed a remote attacker to inject arbitrary scripts or HTML (UXSS) via a crafted HTML page.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 05/06/2023
The vulnerability identified as CVE-2017-15429 represents a critical cross-site scripting flaw within Google Chrome's V8 JavaScript engine WebAssembly implementation. This issue specifically affects the JavaScript bindings used to interact with WebAssembly modules, creating a pathway for remote attackers to execute malicious code through carefully crafted HTML pages. The vulnerability stems from an improper handling of user input within the WebAssembly JavaScript interface, allowing attackers to bypass standard security mechanisms that typically protect against such attacks. The flaw exists in Chrome versions prior to 63.0.3239.108, making a substantial user base vulnerable to exploitation.
The technical root cause of this vulnerability lies in the insufficient validation and sanitization of data passed between JavaScript and WebAssembly contexts. When Chrome processes WebAssembly modules through its JavaScript bindings, the system fails to properly escape or validate input parameters that could contain malicious scripts or HTML content. This inadequate input handling creates a vector for cross-site scripting attacks where attacker-controlled data can be injected directly into the page's execution context. The vulnerability specifically enables Universal Cross-Site Scripting (UXSS) attacks, which are particularly dangerous because they can bypass traditional security measures and affect users across different domains.
The operational impact of this vulnerability extends beyond typical XSS scenarios, as it leverages the powerful capabilities of WebAssembly to execute arbitrary code within the browser environment. Attackers can craft malicious HTML pages that, when loaded by victims, trigger the vulnerable WebAssembly JavaScript bindings and execute unauthorized scripts or HTML content. This creates significant risks for users who visit compromised websites or click on malicious links, as the attack can potentially steal session cookies, perform unauthorized actions on behalf of users, or redirect them to phishing sites. The vulnerability affects not only individual users but also enterprise environments where Chrome is widely deployed, potentially compromising entire organizational security postures.
Security mitigations for this vulnerability require immediate patching of affected Chrome versions to 63.0.3239.108 or later, which incorporates proper input validation and sanitization within the WebAssembly JavaScript bindings. Organizations should implement comprehensive browser security policies that include automatic updates, regular security assessments, and monitoring for suspicious activities. The vulnerability aligns with CWE-79, which describes cross-site scripting flaws, and maps to ATT&CK technique T1059.007 for script execution through web browsers. Additional defensive measures include implementing Content Security Policies, using browser security extensions, and conducting regular security training for users to recognize potential phishing attempts that might exploit such vulnerabilities. Organizations should also consider network-level protections such as web application firewalls and intrusion detection systems to monitor for exploitation attempts.