Skill UI

This skill guides the detection and exploitation of JavaScript prototype pollution vulnerabilities. It covers both client-side (DOM XSS) and server-side (RCE, Auth Bypass) attacks by injecting properties into Object.prototype using keys like `__proto__`. Use this when assessing APIs that deep-merge or clone user-controlled JSON data, or for general web application security testing.

This comprehensive playbook details advanced techniques for detecting Prototype Pollution vulnerabilities in JavaScript environments (Node.js and browser). It covers various attack vectors, including using `__proto__` and `constructor.prototype` paths, and provides black-box testing payloads for JSON parsing, query string merging, and deep object assignment. Use this when analyzing applications for potential Remote Code Execution (RCE) or unintended property leakage via object merging sinks.

This advanced playbook covers escalating prototype pollution into Remote Code Execution (RCE) and Cross-Site Scripting (XSS). It details exploitation techniques across various environments, including Node.js child_process, EJS, Pug, Handlebars, and client-side libraries like jQuery and Lodash. It is designed for security researchers and penetration testers to systematic locate and exploit deep merge sinks and framework gadgets.