What happened
void.cash (VCASH) was an Ethereum token whose owner can switch trading off for everyone except itself. While limitsEnabled is true, pauseTrading makes every transfer between two addresses that are not fee-excluded revert with ErrTradingNotActive, which covers any holder selling into the Uniswap pair, while transfers from or to the owner skip all limit checks. CertiK reported that trading on the token had been paused since 21 March 2023.
On 2023-04-23 the deployer, which is also the contract owner on-chain today, sold 70,418,494.24 VCASH into the pool for about 18.804 ETH, which CertiK flagged as an exit scam. The record values the loss at about USD 34,148.
How it happened
- The deployer is the owner and the hard-coded
devWallet, and the constructor excludes it from fees and max-transaction limits. - In
_transfer,bool isOwner = from == owner() || to == owner();and the limit block runs onlyif (limitsEnabled && !isSwapping && !isOwner && !isBurning), so the owner's transfers bypass every limit. - Inside that block,
if (!tradingEnabled) { if (!isExcludedFromFees[from] && !isExcludedFromFees[to]) { revert ErrTradingNotActive(); } }blocks ordinary holders, because neither they nor the pair are fee-excluded. pauseTradingis anonlyOwnerfunction that setstradingEnabled = false, and the owner can call it at any time. CertiK reported that trading had been paused since 21 March 2023.- On 2023-04-23 at 04:06 UTC the deployer sold 70,418,494.24
VCASHthrough the Uniswap Universal Router and received about 18.804 WETH (tx 0x552e65b7…d144f6).
Protocol details
Evidence
- report CertiK Alert on X: exit scam of Void.Cash twitter.com
- transaction Etherscan tx 0x552e65b7... deployer VCASH sale etherscan.io
- address void.cash (VCASH) VoidCashV2 verified contract source, Etherscan etherscan.io
- address etherscan.io address 0xbd6b…0e7c etherscan.io
- analysis Sourcify match, chain 1, 0x37cd4E8875E3EDafFDFe9Be63958f07eFfBD0Bfd repo.sourcify.dev
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