Blind Signing
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In Brief
Blind signing is approving a crypto transaction you can't fully read or verify — the wallet shows raw data instead of a human-readable action, so you can't be sure what you're authorizing. Clear signing is the safer opposite.
What Is Blind Signing?
Blind signing means authorizing a transaction or message without being able to see, in plain language, what it actually does. Instead of "Send 100 USDT to Alice," the wallet shows an unreadable blob of contract data — and you approve it on faith. Most major drainer thefts start with a blind signature on a malicious site.
The opposite is clear signing (human-readable signing): the wallet decodes the request and shows the real action — what moves, where, and what permissions are granted — before you approve.
Why Blind Signing Is Dangerous
A signature is authorization. Whatever the data says — a transfer, an unlimited token approval, an NFT listing — your signature makes it valid.
Malicious dApps rely on unreadable requests: what looks like a harmless login can be an approval handing an attacker your tokens.
Complex DeFi interactions make people click through data they don't understand — attackers count on that habit.
How to Protect Yourself
Prefer readable requests. If your wallet can't decode what a site is asking, treat it as a red flag.
Reject anything you can't explain in one sentence.
Check the simulation. Modern wallets preview a transaction's effect — balance changes, approvals — before you sign.
Segment funds so one bad signature can't reach everything.
Blind Signing and Trust Wallet
Trust Wallet's Security Scanner simulates and screens transactions, surfacing what a request will actually do and warning on known-malicious contracts before you sign — turning blind approvals into informed decisions while your keys stay in your hands.