What Is a Malicious Signature Request in Crypto?

Signature requests don't cost gas or touch the blockchain — which makes them feel harmless. Here's why some can be just as dangerous as a transaction.

Published: September 13, 2026
Updated: September 13, 2026

Not every dangerous action in crypto involves an obvious on-chain transaction. Some of the most effective scams use signature requests instead — a different, often less understood category of request that can be just as damaging while looking, to an inexperienced eye, less significant than a transaction.

The Difference Between a Transaction and a Signature

A transaction is broadcast to the blockchain immediately, costs a gas fee, and directly changes something on-chain. A signature is something you create off-chain — it doesn't cost gas and simply proves you authorized a specific piece of data.

Why Signatures Can Still Be Dangerous

A signature's danger comes from what it can later be used for. Certain types of signatures — particularly Permit and Permit2 — can grant the same practical effect as an on-chain token approval, achieved off-chain instead.

Why This Format Makes Malicious Requests Harder to Spot

Because signing doesn't cost gas, a malicious signature request can be framed as something trivial — the absence of a fee can be mistaken for an absence of risk.

What a Wallet's Signature Prompt Actually Shows

A signature request prompt may show raw, difficult-to-read data rather than a clear summary of what's being authorized.

What a Malicious Signature Can Lead To

Depending on the type requested, the consequence can range from a targeted approval to a broader Permit2-based authorization allowing a contract to transfer multiple assets.

What to Actually Do

Treating any signature request with the same scrutiny as a transaction closes the gap that "it's just a signature" creates.

Check the contract or site requesting a signature before signing — a free, gas-less request isn't automatically a low-risk one.