Definition
A dust attack (or dusting attack) is a privacy assault in which an adversary sprays minuscule amounts of Bitcoin — often just a few hundred satoshis, near the network's dust threshold of about 546 sats — across thousands of addresses. The dust itself is economically worthless. Its purpose is purely to plant a tracking beacon in your wallet.
How Deanonymization Happens
Because Bitcoin tracks balances as discrete UTXOs, that dust sits in your wallet as its own coin. If your wallet later bundles it into a payment alongside your other UTXOs, the common-input-ownership heuristic lets the attacker link every address whose coins shared that transaction into a single cluster. Pair that cluster with any identifying event — a KYC exchange withdrawal, a doxed donation address — and the analyst can attach a real-world identity to the whole group. The attack is behavioral: it only works if you spend the dust.
Protecting Yourself
The defense is simple: do not spend the dust. Many self-custody wallets support coin control, letting you see individual UTXOs and exclude or freeze suspicious ones so they never get selected for a transaction. Marking dust as "do not spend" neutralizes the beacon. Running coin-control-capable software and reviewing your UTXO set is a core sovereignty habit, especially for anyone receiving payments from the public.
For related defenses, see our entries on the Common-Input-Ownership Heuristic and UTXO Consolidation.
In Simple Terms
A dust attack (or dusting attack) is a privacy assault in which an adversary sprays minuscule amounts of Bitcoin — often just a few hundred…