MESSI - Smart Contract Audit Report

Summary

MESSI Audit Report MESSI is a new DeFi token with frictionless fee redistribution and a buyback system for burning supply.

We audited MESSI's token contract at 0xa86d9919a8fff0852c57786e600987ecef17227c on the Ethereum Block Chain mainnet.

Overview of the Contract:
  • The total supply of the token is set to one trillion [1,000,000,000,000] $MESSI.
  • No mint or burn functions are present; though the circulating supply can be reduced by sending tokens to the 0x..dead address, if desired.
  • At the time of writing this report, 100% of the total supply is in possession of the owner as the project was recently deployed.

  • There is a "tax fee" and "liquidity fee" on all transactions for any non-excluded address that participates in a transfer. The owner has the ability to modify these fees to any percentage at any time.
  • Users who hold tokens will automatically benefit from the frictionless fee redistribution at the time of each transaction as the tokens collected through taxes are removed from the circulating supply.
  • The funds collected from the liquidity fee on transactions are stored in the contract. Once a threshold value is met, the tokens are swapped for ETH and a portion is sent to the project team's "rival" wallet. This rival allocation can be modified to an uncapped percentage determined by the owner, and the address of the rival wallet can be changed by the owner at any time.
  • When buyback functionality is enabled a portion of the remaining ETH balance will be swapped for tokens and then subsequently burned.

  • The owner of the contract can exclude and include accounts from transfer fees and reward distribution.
  • The owner of the contract can toggle the buyback functionality.
  • The contract features a presale where the transaction liquidity fee is set to 90 and the maximum transaction amount is set to the total $MESSI token supply.
  • The owner has the ability to set and update a maximum transaction percent at any time, which will impose a limit to the number of tokens that can be transferred during any given transaction.
  • This maximum transaction amount does not apply to the owner during transactions where the owner is either the sender or the recipient.
  • The owner has the ability to use the "lock" function in order to temporarily set ownership to address(0). Ownership is restored after the duration of time determined by the owner has passed and they use the 'unlock' function. Ownership can additionally be restored (even if ownership was previously renounced), by using the unlock function a second time.
  • The owner has the ability to transfer and renounce ownership if desired.
  • Ownership has not been renounced.

  • Some state variables could have been declared constant to save some gas upon deployment.
  • Some functions could have been declared external instead of public to save on gas upon deployment.
  • The contract utilizes SafeMath libraries along with following the ERC20 standard.
  • As the project is deployed with Solidity v0.8.4, it is protected from overflows.

Audit Findings Summary
  • Buyback functionality may be suseptible to front-running; The team must monitor and if suspicious activity is detected, the team must disable the buyback system.
  • We strongly recommend renouncing ownership after a successful deployment.
  • Ensure trust in the team as they have significant control in the ecosystem; as they can modify fees to any percentage in addition to the allocated portion of ETH that goes to the rival wallet upon utilizing the 'buyback' functionality.
  • Date: July 8th, 2021

Vulnerability CategoryNotesResult
Arbitrary Storage WriteN/APASS
Arbitrary JumpN/APASS
Delegate Call to Untrusted ContractN/APASS
Dependence on Predictable VariablesN/APASS
Deprecated OpcodesN/APASS
Ether ThiefN/APASS
ExceptionsN/APASS
External CallsN/APASS
Flash LoansN/APASS
Integer Over/UnderflowN/APASS
Multiple SendsN/APASS
OraclesN/APASS
SuicideN/APASS
State Change External CallsN/APASS
Unchecked RetvalN/APASS
User Supplied AssertionN/APASS
Critical Solidity CompilerN/APASS
Overall Contract Safety PASS

BEP20 Token Graph

Multi-file Token

												
($) = payable function
 # = non-constant function

 +  Context 
    - [Int] _msgSender
    - [Int] _msgData

 + [Int] IERC20 
    - [Ext] totalSupply
    - [Ext] balanceOf
    - [Ext] transfer #
    - [Ext] allowance
    - [Ext] approve #
    - [Ext] transferFrom #

 + [Lib] SafeMath 
    - [Int] add
    - [Int] sub
    - [Int] sub
    - [Int] mul
    - [Int] div
    - [Int] div
    - [Int] mod
    - [Int] mod

 + [Lib] Address 
    - [Int] isContract
    - [Int] sendValue #
    - [Int] functionCall #
    - [Int] functionCall #
    - [Int] functionCallWithValue #
    - [Int] functionCallWithValue #
    - [Prv] _functionCallWithValue #

 +  Ownable (Context)
    - [Pub]  #
    - [Pub] owner
    - [Pub] renounceOwnership #
       - modifiers: onlyOwner
    - [Pub] transferOwnership #
       - modifiers: onlyOwner
    - [Pub] getUnlockTime
    - [Pub] getTime
    - [Pub] lock #
       - modifiers: onlyOwner
    - [Pub] unlock #

 + [Int] IUniswapV2Factory 
    - [Ext] feeTo
    - [Ext] feeToSetter
    - [Ext] getPair
    - [Ext] allPairs
    - [Ext] allPairsLength
    - [Ext] createPair #
    - [Ext] setFeeTo #
    - [Ext] setFeeToSetter #

 + [Int] IUniswapV2Pair 
    - [Ext] name
    - [Ext] symbol
    - [Ext] decimals
    - [Ext] totalSupply
    - [Ext] balanceOf
    - [Ext] allowance
    - [Ext] approve #
    - [Ext] transfer #
    - [Ext] transferFrom #
    - [Ext] DOMAIN_SEPARATOR
    - [Ext] PERMIT_TYPEHASH
    - [Ext] nonces
    - [Ext] permit #
    - [Ext] MINIMUM_LIQUIDITY
    - [Ext] factory
    - [Ext] token0
    - [Ext] token1
    - [Ext] getReserves
    - [Ext] price0CumulativeLast
    - [Ext] price1CumulativeLast
    - [Ext] kLast
    - [Ext] burn #
    - [Ext] swap #
    - [Ext] skim #
    - [Ext] sync #
    - [Ext] initialize #

 + [Int] IUniswapV2Router01 
    - [Ext] factory
    - [Ext] WETH
    - [Ext] addLiquidity #
    - [Ext] addLiquidityETH ($)
    - [Ext] removeLiquidity #
    - [Ext] removeLiquidityETH #
    - [Ext] removeLiquidityWithPermit #
    - [Ext] removeLiquidityETHWithPermit #
    - [Ext] swapExactTokensForTokens #
    - [Ext] swapTokensForExactTokens #
    - [Ext] swapExactETHForTokens ($)
    - [Ext] swapTokensForExactETH #
    - [Ext] swapExactTokensForETH #
    - [Ext] swapETHForExactTokens ($)
    - [Ext] quote
    - [Ext] getAmountOut
    - [Ext] getAmountIn
    - [Ext] getAmountsOut
    - [Ext] getAmountsIn

 + [Int] IUniswapV2Router02 (IUniswapV2Router01)
    - [Ext] removeLiquidityETHSupportingFeeOnTransferTokens #
    - [Ext] removeLiquidityETHWithPermitSupportingFeeOnTransferTokens #
    - [Ext] swapExactTokensForTokensSupportingFeeOnTransferTokens #
    - [Ext] swapExactETHForTokensSupportingFeeOnTransferTokens ($)
    - [Ext] swapExactTokensForETHSupportingFeeOnTransferTokens #

 +  MESSI (Context, IERC20, Ownable)
    - [Pub]  #
    - [Pub] name
    - [Pub] symbol
    - [Pub] decimals
    - [Pub] totalSupply
    - [Pub] balanceOf
    - [Pub] transfer #
    - [Pub] allowance
    - [Pub] approve #
    - [Pub] transferFrom #
    - [Pub] increaseAllowance #
    - [Pub] decreaseAllowance #
    - [Pub] isExcludedFromReward
    - [Pub] totalFees
    - [Pub] minimumTokensBeforeSwapAmount
    - [Pub] buyBackUpperLimitAmount
    - [Pub] deliver #
    - [Pub] reflectionFromToken
    - [Pub] tokenFromReflection
    - [Pub] excludeFromReward #
       - modifiers: onlyOwner
    - [Ext] includeInReward #
       - modifiers: onlyOwner
    - [Prv] _approve #
    - [Prv] _transfer #
    - [Prv] swapTokens #
       - modifiers: lockTheSwap
    - [Prv] buyBackTokens #
       - modifiers: lockTheSwap
    - [Prv] swapTokensForEth #
    - [Prv] swapETHForTokens #
    - [Prv] addLiquidity #
    - [Prv] _tokenTransfer #
    - [Prv] _transferStandard #
    - [Prv] _transferToExcluded #
    - [Prv] _transferFromExcluded #
    - [Prv] _transferBothExcluded #
    - [Prv] _reflectFee #
    - [Prv] _getValues
    - [Prv] _getTValues
    - [Prv] _getRValues
    - [Prv] _getRate
    - [Prv] _getCurrentSupply
    - [Prv] _takeLiquidity #
    - [Prv] calculateTaxFee
    - [Prv] calculateLiquidityFee
    - [Prv] removeAllFee #
    - [Prv] restoreAllFee #
    - [Pub] isExcludedFromSwapFee
    - [Pub] excludeFromSwapFee #
       - modifiers: onlyOwner
    - [Pub] includeInSwapFee #
       - modifiers: onlyOwner
    - [Pub] isExcludedFromFee
    - [Pub] excludeFromFee #
       - modifiers: onlyOwner
    - [Pub] includeInFee #
       - modifiers: onlyOwner
    - [Ext] setTaxFeePercent #
       - modifiers: onlyOwner
    - [Ext] setLiquidityFeePercent #
       - modifiers: onlyOwner
    - [Ext] setMaxTxAmount #
       - modifiers: onlyOwner
    - [Ext] setRivalDivisor #
       - modifiers: onlyOwner
    - [Ext] setNumTokensSellToAddToLiquidity #
       - modifiers: onlyOwner
    - [Ext] setBuybackUpperLimit #
       - modifiers: onlyOwner
    - [Ext] setRivalContract #
       - modifiers: onlyOwner
    - [Pub] setSwapAndLiquifyEnabled #
       - modifiers: onlyOwner
    - [Pub] setBuyBackEnabled #
       - modifiers: onlyOwner
    - [Ext] prepareForPreSale #
       - modifiers: onlyOwner
    - [Ext] afterPreSale #
       - modifiers: onlyOwner
    - [Prv] transferToAddressETH #
    - [Ext]  ($)