On-chain Safety Education
Onchain Diary is an independent Web3 safety education site: 119 deep-dive articles, a 232-term glossary, and the complete BIP-39 wordlist: covering crypto scams, smart contract security, and on-chain analysis. No jargon. No sign-up. No tools to install. Just the knowledge you need to stop getting rekt.
Guides, tutorials, and deep dives.
A hacker ran 14 million queries against Denmark's national register for ten days through a small IT firm whose admin account used the password 123456. What 8.8 million leaked identities mean for crypto users.
A buyer found hardware implants in two Ledger Nano X wallets bought at different MediaMarkt stores in Europe. Mark Karpelès identified the devices as carrying an earlier implant design — with an antenna labeled 'Eurasian version.' Within 48 hours, MediaMarktSaturn delisted Ledger group-wide, Ledger asked Southeast Asia and Hong Kong resellers to halt sales, and Bitquery's tally reached $102 million. Here is what is verified and what isn't.
An email shows an old password you actually used, claims malware recorded you through your webcam, and gives a Bitcoin address with a 48-hour countdown. Here is what on-chain research and FBI guidance say about these campaigns, the 2026 named-crew upgrade that adds real breach data, and exactly what to do in the first hour.
The fake 'FMMR Mining' pool farmed 151 wallets for over 1.5M USDC; every victim signed a 10M-USDC permit valid until 2030. Original domain fmmrvip.click is dead — fmmrvip.space is the same scam, registered the same day, now ranking on Google page one for its own name.
An authorized Ledger reseller was secretly acquired, its devices implanted, and an estimated $72M–$90M drained from buyers. The full timeline of a textbook supply-chain takeover.
How fake crypto job offers work: the Bybit/Safe breach, malicious coding tests, and the red flags every Web3 job seeker should know.
Reading is half. The other half is recall.
Every question is drawn strictly from the Yellow Paper's own text. No outside knowledge required: if you've read it, you can pass it.
Take the quiz → T-02Sixteen scenario questions sort you into one of sixteen security personas: hunter or prey: with a safety index and a shareable result card.
Find your type →A few terms to get you going: the full glossary has 232+.
Whether you're new to crypto or deep into DeFi, understanding how scams work is the best defense. Every guide here is free.
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