What happened
Walletreum (WALT) was promoted as a crypto asset-management and lending project. Its ERC-20 token on Ethereum at 0x15bCDFAd…33bd25 uses OpenZeppelin's ERC20Mintable, which lets any holder of the minter role create unlimited WALT. The deployer, 0xa5e552e3…aeE775, holds that role from deployment and can grant it to others.
On 15 November 2020 the deployer called mint to create 500,000,000,000 WALT for the wallet 0x665f3841…29d358, ten thousand times the 50,000,000 supply that existed before. The wallet swapped the new tokens on Uniswap V2 for about 138,439 USDT, and the next day swapped that USDT for 298.12 ETH. De.Fi's REKT database lists the loss as $138,340.
According to that listing, the ETH was later swapped for 156,120 USDT and sent to Binance.
How it happened
MinterRole's constructor runs_addMinter(_msgSender()), so the deployer is a minter from the start, andaddMinter(address account) public onlyMinterlets any minter add more minters.mint(address account, uint256 amount) public onlyMintercalls_mint, which runs_totalSupply = _totalSupply.add(amount);with no maximum supply. A minter can create any amount at any time.- On 15 November 2020 at 18:53:09 UTC the deployer called
mintfor 500,000,000,000 WALT to 0x665f3841…29d358 in transaction 0xc0f3b057…4710e5. The on-chain supply now reads 500,050,000,000 WALT. - The same day, that wallet made a series of Uniswap V2 swaps. De.Fi's listing says these sold the minted WALT for 138,439 USDT, taking the value that holders had placed in the pools.
- On 16 November 2020 the wallet swapped 138,439.64 USDT for 298.12 ETH in transaction 0xc47c26a8…6e7f15. De.Fi lists a later swap to 156,120 USDT (0xe20d10e7…fce7ac) and Binance deposits including 0xf9cf08f5…0f221f and 0xcce3eacb…7217f9.
Protocol details
Evidence
- transaction WALT mint transaction etherscan.io
- transaction USDT to ETH swap by 0x665F38... etherscan.io
- transaction etherscan.io transaction 0xcce3…17f9 etherscan.io
- transaction etherscan.io transaction 0xe20d…e7ac etherscan.io
- transaction etherscan.io transaction 0xf9cf…221f etherscan.io
- address Walletreum (WALT) verified source code etherscan.io
- address Address 0x665F384184A20FA92eCDF87F52d76d25FA29d358 etherscan.io
- address etherscan.io address 0xa5e5…e775 etherscan.io
- analysis De.Fi proof link (archive.ph snapshot) archive.ph
- analysis de.fi Analysis t.me
- analysis Web Archive web.archive.org
- analysis Sourcify match for 0x15bCDFAd12498DE8a922E62442Ae4CC4bd33bd25 on Ethereum repo.sourcify.dev
- analysis bloxy.info page 0x665f…d358 bloxy.info
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