Wallet drainer
Plain definition. A wallet drainer is a malicious Web3 scam that tricks you into approving a transaction, permission or signature that lets an attacker move your tokens or NFTs.
Technical definition. In an April 13, 2026 explainer, the walllet team defines a wallet drainer as a malicious site, script or contract flow built to empty a crypto wallet once the victim approves something that looks harmless, often without breaking the wallet or stealing the seed phrase first. It typically obtains a token approval that lets a contract spend ERC-20 tokens, an NFT approval such as setApprovalForAll, or a signed message that can later become an approval or transfer through permit-style mechanisms. Once the user confirms, the drainer script or malicious contract uses the granted permission to move assets out.
On this site
On this site, Wallet drainer comes up in What is a malicious signing request or wallet drainer? and Why are there strange tokens, airdrops or messages in my XRP wallet, and should I claim them?.
Source
What Is a Wallet Drainer? How These Attacks Work and How to Avoid Them | walllet.com (walllet.com), read October 1, 2026.