client side
Client-side vulnerabilities: DOM manipulation, postMessage, prototype pollution.
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Client-side vulnerabilities: DOM manipulation, postMessage, prototype pollution.
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1Advanced level
4Client-side admin bypass — boolean manipulation + BAC in a modern SPA
Real Quora report: SPA with an isAdmin boolean in localStorage that controls the UI + a backend that doesn't validate server-side. How to chain a boolean flip with BAC for admin takeover.
DOM XSS — gadgets, postMessage handlers and CVE-2025-59840
DOM XSS isn't just innerHTML. Sources/sinks, gadget chains via toString(), postMessage handlers without origin checks, broken hash-based routing.
DOM XSS — sources, sinks and gadgets to chain filter bypasses
A complete map of sources (location, postMessage, document.referrer, localStorage) and sinks (innerHTML, eval, document.write, jQuery $.html) + gadgets to build undetectable payloads.
Prototype Pollution — from malicious JSON to XSS, RCE and auth bypass
How an attacker pollutes Object.prototype and breaks the code's assumptions. Client-side and server-side vectors, gadgets in lodash/jQuery/Angular.
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