Voting power is read from current token balance, so an attacker flash-borrows governance tokens, creates and/or votes on a proposal, and returns the loan — capturing governance in one block.
// ERC20Votes: weight = getPastVotes(voter, proposalSnapshotBlock)
uint256 w = token.getPastVotes(msg.sender, proposals[id].snapshot);
tally[id] += w;
Incidents this entry cites by name:
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