CTF Walkthrough: Prototype Pollution from Client-Side to RCE (BLEACH Enterprise)
A few weeks ago, this CTF from XDMIRROR popped up on my feed: a mock corporate IT management panel called BLEACH Enterprise built entirely around prototype pollution. Five distinct gadgets, spanning from client-side DOM XSS and open redirects all the way to server-side auth bypass, SSRF, and full RCE in Node.js—all exploiting the exact same root cause vuln..
Read moreClient-Side Hacking Curiosities (2025 edition)
Been accumulating a list of client-side weirdness all year. Things that surprised me, techniques I found while reading specs, and browser behaviours that look benign on paper but get interesting when you think adversarially. No particular order, no particular coherence — just a dump of things worth knowing if you spend time attacking or defending browser e..
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Weaponizing JavaScript II: Client-Side FUZZING
Client-Side Fuzzing: A JavaScript Approach for Web Vulnerability TestingClient-side fuzzing can be a fascinating approach to discovering web vulnerabilities by leveraging the browser’s capabilities to test for issues such as SQL Injection (SQLi) and Cross-Site Scripting (XSS). This post explores a JavaScript code snippet designed to perform fuzzing dire..
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Cl13nt SId3 H4cKing Introduction
In this article we will introduce some basic concepts to understand the hacking techniques used against browsers focused on their “Client-Side”. JavaScript is a programming language that is commonly used in web development. It is a client-side scripting language, which means that it is executed by the user’s web browser rather than on a server. JavaScript..
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