Monster333 — 401/403 bypass testing with control requests

Monster333 is a Python CLI for testing access-controlled routes with trust headers, path and encoding variants, HTTP method changes, and separate raw probes for h2c and request smuggling.

Capabilities: • runs 318 request variants across 13 technique groups; • compares responses with the blocked baseline and a random path; • rejects known WAF block pages and behavior reproduced by harmless control headers; • replays stable 2xx candidates; • writes JSON, Markdown, and HTML reports with a reproducible curl command.

Its useful distinction is the validation sequence around each candidate. These checks reduce routine response noise but cannot guarantee zero false positives; h2c and request-smuggling signals still require manual confirmation.

Tool: https://github.com/shafiquljob333-rgb/monster333