exploiting-prototype-pollution-in-javascript

To test for prototype pollution in JavaScript applications, scan target URLs or local JS files for vulnerable deep-merge gadget paths using URL parameters and JSON bodies to identify sources, sinks, and assess gadget viability.

Prototype pollution is a web security vulnerability where attackers inject properties into JavaScript object prototypes. It affects web security by enabling Cross-Site Scripting (XSS) or Remote Code Execution (RCE) through compromised client-side and server-side merge patterns.

Yes, you can detect server-side prototype pollution gadgets in Node.js by testing target URLs and JSON bodies against common deep-merge patterns and template engines to assess gadget viability and identify vulnerable code.

Prototype pollution testing works for both client-side and server-side contexts. It detects vulnerable patterns via URL parameters and JSON bodies, identifying sources and sinks across the entire JavaScript application stack.

The best way to remediate prototype pollution vulnerabilities is to scan code for vulnerable deep-merge patterns and utilize generated remediation recommendations to block malicious property injection at the source before production deployment.

Prototype pollution scanning might fail to find vulnerable gadget paths if the target JavaScript application uses non-standard deep-merge implementations or sanitizes URL parameters and JSON bodies before processing them.