Dust attacks

In plain words

Dust is a few worthless satoshis sent, unasked, to thousands of addresses. It isn't a gift. The sender watches: when your wallet later spends the dust together with your real coins, the merge links your addresses into one cluster — free intelligence for whoever is mapping the chain. Receiving dust costs you nothing and proves nothing. The trap only springs when you spend it. So don't: label it, freeze it, forget it.

Why it matters

• Anyone can send coins to your address; your defense is refusing to spend them.
• Modern wallets can freeze suspect coins — coin control is the antidote.
• A cheap attack that works in bulk: thousands dusted at once.

Go deeper

• Coin control
• Chain analysis
• UTXO