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What is a wallet drainer?
A wallet drainer is malicious code, usually behind a fake website, that tricks you into connecting your wallet and approving a transaction or permission. Once approved, it moves your coins, tokens and NFTs to wallets the criminals control, sometimes immediately and sometimes later.
What it means for you
A drainer does not need your seed phrase; one signature granting spending permission can be enough, and that permission can stay open after you leave the site. Read what a wallet prompt is asking before you sign, and revoke approvals you no longer use. Assets taken this way are usually moved quickly and are rarely recovered.
A common mistake: “I never shared my seed phrase, so my wallet cannot be emptied.”
In fact: A drainer needs only a signature granting spending permission. The permission can stay open after you leave the site, and it lets the contract move approved assets without ever knowing your seed phrase.
How it works
A typical run, as the FBI describes it: criminals hijack or clone a project's social media account and post an urgent "limited supply" mint or claim. The link opens a spoofed site that asks you to connect a wallet and approve a transaction. That approval authorises the drainer contract to move your coins and NFTs, often at once. Because token approvals stay in force until revoked, a contract can keep draining a wallet later as new assets arrive. Stolen assets are usually passed through mixers and exchanges to hide where they went. Revoking old approvals stops further draining through them.
Sources: FBI IC3: Cyber criminals impersonating NFT developers to steal cryptocurrency (PSA230804), ethereum.org: Scam help and reporting · checked 4 October 2026
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Educational content, not financial advice. Written by hand and checked against the source named above. Something wrong? Tell us and we reply within two business days.