KingCorgi Honeypot
What happened
KingCorgi ($KngCG) on BNB Smart Chain, contract 0x83fa57c0…12e886, stores an address in newun and reverts any transfer or transferFrom whose recipient is that address with the message please wait. newun is empty at deployment and is filled by the first transferFrom call, with whatever recipient that call has. If that first call is the one that supplies liquidity to a trading pair, the pair becomes the blocked recipient, so later sells into it revert while buys out of it do not meet the check.
Only the owner's transfernewun can change the stored address. De.Fi's REKT database lists the token as an exit scam/honeypot and says the contract owner could disable transfers, which restricted users from selling; a write-up in its proof field describes this same newun pattern in other BSC tokens.
How it happened
- At deployment the
Ownedconstructor setsowner = msg.senderand the whole supply goes to the owner.newunis empty. - The first
transferFromwith a non-zerofromrunsif(from != address(0) && newun == address(0)) newun = to;. It records the recipient and then moves the tokens, with no check on who the recipient is. If this call is the liquidity add, the stored address is the pair. - After that, every
transferFromtakes theelsebranch:else require(to != newun, "please wait");, andtransferhas its ownrequire(to != newun, "please wait");. A sell through a router is atransferFrom(holder, pair, amount), so withnewunset to the pair the call reverts and the holder's balance is not debited. - Transfers whose recipient is any other address still work, for example a pair paying out to a buyer, which is why the token can look tradable from the buy side.
- The owner controls the block:
function transfernewun(address _newun) public onlyOwner { newun = _newun; }. Setting it to the zero address re-arms the capture at the nexttransferFrom; pointing it at an address nobody uses lifts the block. The contract has norenounceOwnership, onlytransferOwnershipandacceptOwnership. - What happened: De.Fi's REKT database lists the token as an exit scam/honeypot dated 2021-06-02. No opened source shows the value of
newun, any failed sell, or any loss figure.
Protocol details
Evidence
- report De.Fi REKT database listing for $KngCG (as supplied; proof tweet returned 404) twitter.com
- address KingCorgi ($KngCG) verified source code, BscScan bscscan.com
- analysis Scam explained: BSC stealthy LP block (cryptot3ddybear) cryptot3ddybear.gitlab.io
- analysis Sourcify repository entry for 0x83fa57c046263ead0fafbeef81277a654c12e886 repo.sourcify.dev
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