hard20 pts · first answer countssmart-contract-securitysignaturestokens

A permit call that silently succeeds

A bridge calls token.permit(...) and then transferFrom(victim, ...) for any token. For WETH, which has no permit but has a fallback that accepts calls, what goes wrong?

A.permit reverts, so no tokens can be bridgedB.permit silently succeeds, so old approvals can be drainedC.WETH converts the permit into a deposit of ETHD.The bridge receives the victim's ETH instead

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A permit call that silently succeeds

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