What happened
CUATRO is a BEP-20 token on BNB Smart Chain whose transfer logic contains an owner-controlled sell block. The owner can flag any address with setPanCakeSwapReciever, and from then on every transfer into that address reverts with "Error: Can not sell this token". Flagging a trading pair's address would make selling to that pair impossible while buying stays unaffected.
De.Fi's REKT database lists the token as an Exit Scam/Honeypot dated 2021-04-03 and describes it as a contract whose owner could disable the transfer function, which restricted users in selling their tokens. The code shows the control exists; the listing's proof post could not be opened, so which address was flagged, and when, is not established here.
How it happened
- The constructor mints the whole supply to the deployer:
_transferTO(msg.sender, 4000000e18);. TheOwnablebase contract also makes the deployer the owner (_owner = _msgSender();). - Every
transferandtransferFromruns_transfer, which debits the sender and then callscalculateFeesBeforeSend(sender, recipient, amount). - That function reverts for any flagged recipient:
if(PanCakeSwapReciever[recipient]){ revert("Error: Can not sell this token"); }. Otherwise it returns(amount, 0). There is no exemption for the sender, so the owner's own transfers to a flagged address revert too. - The flag is set by an owner-only function with no limit in the code:
function setPanCakeSwapReciever(address _recipient, bool _feeless) public onlyOwnerwritesPanCakeSwapReciever[_recipient] = _feeless;. Passingfalseclears it again, so the block can be switched on and off. - If the owner flags the address that receives tokens when a holder sells, the holder's sell transaction reverts and the whole transaction, including the balance debit, is rolled back. Transfers to unflagged addresses keep working, so ordinary wallet-to-wallet transfers and buys look normal.
renounceOwnership()exists, so the owner could give the power up. Aneth_callread on 2026-09-30 still returned the deployer as owner.
Protocol details
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