Exercises

Exercise Avg. Time Difficulty Solved by Tier
JS Sandbox: Regex Filter Bypass
This exercise covers bypassing regex filters with hex escapes, unicode escapes, or base64 decoding.
< 1 Hr. medium 28 PRO
JS Sandbox: vm.runInNewContext Empty Context
This exercise covers escaping Node.js vm.runInNewContext with an empty sandbox object via the constructor chain.
-- medium 22 PRO
JS Sandbox: AST-Based Filtering
This exercise covers bypassing AST-based sandbox filtering using computed property access or Reflect.get().
-- medium 24 PRO
JS Sandbox: Type Confusion Bypass
This exercise covers bypassing string sanitization by sending an object when the sanitizer expects a string.
< 1 Hr. medium 23 PRO
CVE-2026-XX27
This challenge covers the review of a CVE in a javascript codebase and its patch
-- hard 42 PRO
CVE-2026-XX822
This challenge covers the review of a CVE in a typescript codebase and its patch
< 1 Hr. hard 45 PRO
CVE-2025-XXXXX
This challenge covers the review of a CVE in a JavaScript codebase and its patch
< 1 Hr. hard 40 PRO
CVE-2026-XX292
This challenge covers the review of a CVE in a typescript codebase and its patch
-- hard 45 PRO
CVE-2024-X7X95
This challenge covers the review of a CVE in a JavaScript codebase and its patch
< 1 Hr. hard 37 PRO
Web Fundamentals: URL Parsing < 1 Hr. hard 182 PRO
Web Fundamentals: Virtual Hosts < 1 Hr. hard 109 PRO
Web Fundamentals: HTTP < 1 Hr. hard 155 PRO
Web Fundamentals: Content Delivery Network < 1 Hr. hard 100 PRO
Web Fundamentals: URL Encoding < 1 Hr. hard 167 PRO
Web Fundamentals: Cookies < 1 Hr. hard 131 PRO
Web Fundamentals: HTML < 1 Hr. hard 151 PRO
Web Fundamentals: JSON < 1 Hr. hard 121 PRO
Web Fundamentals: HTML Forms < 1 Hr. hard 136 PRO
JS Sandbox: Keyword Blocklist Bypass
This exercise covers bypassing indexOf/includes blocklists with bracket notation and string concatenation.
< 1 Hr. medium 32 PRO
JS Sandbox: The Function Constructor
This exercise covers using Function(...)() as an eval alternative to execute arbitrary code in an app that blocks eval.
< 1 Hr. easy 35 PRO
JS Sandbox: Prototype Chain Navigation
This exercise covers navigating __proto__, .constructor, and .prototype from a string literal to reach the Function constructor.
< 1 Hr. easy 43 PRO
JS Sandbox: From Sandbox Escape to RCE
This exercise covers the standard Node.js RCE chain: process -> mainModule -> require('child_process') -> execSync.
< 1 Hr. easy 36 PRO
CVE-2026-XX977
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 64 PRO
CVE-2026-XX953
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 74 PRO
CVE-2026-XX762
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 61 PRO
CVE-2026-XX230
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 63 PRO
CVE-2026-XX928
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 56 PRO
CVE-2026-XX130
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 68 PRO
CVE-2023-51XX9
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 66 PRO
CVE-2026-XX790
This challenge covers the review of a CVE in a python codebase and its patch
< 1 Hr. hard 63 PRO
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Showing 31–60 of 756 exercises