Challenges → API Security

Mass Assignment

Medium 200 pts 🚩 16 solves ⏱ Avg. time to solve: 38d 15h

Challenge Question

This API's registration endpoint accepts a JSON body and builds the new user record straight from whatever fields you send it, with no filtering and no whitelist. See what happens if you include a field the signup form was never designed to expose.
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Details

  • CategoryAPI Security
  • Authortark
  • AddedJul 4, 2026
  • Avg. Time to Solve38d 15h
  • First Blood🩸 ookoro

Recent Solvers

  • piyush69 5d ago
  • Max Oct 18, 2026
  • amalmj Oct 9, 2026
  • V1XU Oct 4, 2026
  • ajay Oct 2, 2026
  • suntzu Aug 18, 2026
  • manideepgarrepelly Aug 16, 2026
  • tkapoor Aug 6, 2026
  • nwilson Aug 3, 2026
  • tark Jul 23, 2026
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