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Life & fun · August 25, 2025

Bitcoin Challenge. Try to steal a plain text private key you can use

Hi HN, I'm releasing my round one public demo of a new browser security system I've been developing. There's a real Bitcoin private key (worth $20) in plaintext at app.redactsure.com. You can copy it, paste it, delete it, move it around - full control. But you can't see the actual characters or extract them. The challenge: Break the protection and take the Bitcoin. First person wins, challenge ends. Details: - Requires email verification (prevents abuse, no account needed) - 15 minute time limit per session - Currently US only for the demo (latency) - Verify the Bitcoin is real:…

Bitcoin Challenge. Try to steal a plain text private key you can use launched on August 25, 2025 with 14 votes, #881 of 8,530 launches that month and more than 75% of that year's launches. The site was still online in September 2026, 1 year on.

Visit app.redactsure.com ↗Alternativestop 10% of August 2025

In plain words

Bitcoin Challenge is a browser security demonstration that hides a real Bitcoin private key in plaintext while allowing full interaction—users can copy, paste, and manipulate it, but cannot view or extract the actual characters. The system uses cloud-hosted browser technology with a real-time model to selectively obscure sensitive data while keeping pages unmodified. Participants have 15 minutes per session to break the protection and claim the private key worth $20. It's designed for security researchers and developers interested in testing novel data protection methods.

written from the facts on this page · September 2026

From the sources

RedactSure replaces sensitive values before an AI agent receives the page. The workflow continues with safe placeholders while the raw data stays outside modelfrom app.redactsure.com

In the maker’s words, at launch

Hi HN, I'm releasing my round one public demo of a new browser security system I've been developing. There's a real Bitcoin private key (worth $20) in plaintext at app.redactsure.com. You can copy it, paste it, delete it, move it around - full control. But you can't see the actual characters or extract them. The…

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