The sell function of a smart contract implementation for ENTER (ENTR) (Contract Name: EnterCoin), an Ethereum token, has an integer overflow in which "amount * sellPrice" can be zero, consequently reducing a seller's assets.

The mintToken function of a smart contract implementation for ENTER (ENTR) (Contract Name: EnterCoin), an Ethereum token, has an integer overflow that allows the owner of the contract to set the balance of an arbitrary user to any value.