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Advanced Manual
Smart Contract Audit

April 28, 2022

Audit requested by

Ethereum Aqua SWAP

0x2015a0c83076f68d76bEd6Af89C38DE2c1c7D650

Ethereum Aqua SWAP / Security Audit

Table of Contents

1. Audit Summary

1.1 Audit scope

1.2 Tokenomics

1.3 Source Code

2. Disclaimer

3. Global Overview

3.1 Informational issues

3.2 Low-risk issues

3.3 Medium-risk issues

3.4 High-risk issues

4. Vulnerabilities Findings

5. Contract Privileges

5.1 Maximum Fee Limit Check

5.2 Contract Pausability Check

5.3 Max Transaction Amount Check

5.4 Exclude From Fees Check

5.5 Ability to Mint Check

5.6 Ability to Blacklist Check

5.7 Owner Privileges Check

6. Notes

6.1 Notes by Coinsult

6.2 Notes by Ethereum Aqua SWAP

7. Contract Snapshot

8. Website Review

9. Certificate of Proof

Ethereum Aqua SWAP / Security Audit

Audit Summary

Audit Scope

Project Name

Ethereum Aqua SWAP

Blockchain

Binance Smart Chain

Smart Contract Language

Solidity

Contract Address

0x2015a0c83076f68d76bEd6Af89C38DE2c1c7D650

Audit Method

Static Analysis, Manual Review

Date of Audit

28 April 2022

This audit report has been prepared by Coinsult’s experts at the request of the client. In this audit, the results of the static analysis and the manual code review will be presented. The purpose of the audit is to see if the functions work as intended, and to identify potential security issues within the smart contract.

The information in this report should be used to understand the risks associated with the smart contract. This report can be used as a guide for the development team on how the contract could possibly be improved by remediating the issues that were identified.

Ethereum Aqua SWAP / Security Audit

Tokenomics

Rank Address Quantity (Token) Percentage
1 0x57b1ecfb40db8a661a372e23c947b3c04c61fdf7 650,300,500 65.0301%
2  0x2015a0c83076f68d76bed6af89c38de2c1c7d650 349,009,000 34.9009%
3 0x943535da485e32f444377c17b9e112f356f68178 101,500 0.0102%
4 0xc79f5228d21dafd1e0fe5f1e87044835319e6ad7 64,000 0.0064%
5 0x63064478972346dfc086ebf9066eccbc6ff0ebe6 60,000 0.0060%

Source Code

Coinsult was comissioned by Ethereum Aqua SWAP to perform an audit based on the following code:
https://bscscan.com/address/0x2015a0c83076f68d76bEd6Af89C38DE2c1c7D650#code

Token sniffer reports:
This token was flagged due to evidence of a bug, hack, or scam:
– Exploit #034: Fake ownership renounce

Check the medium risk issue for more details.

Ethereum Aqua SWAP / Security Audit

Disclaimer

This audit report has been prepared by Coinsult’s experts at the request of the client. In this audit, the results of the static analysis and the manual code review will be presented. The purpose of the audit is to see if the functions work as intended, and to identify potential security issues within the smart contract.

The information in this report should be used to understand the risks associated with the smart contract. This report can be used as a guide for the development team on how the contract could possibly be improved by remediating the issues that were identified.

Coinsult is not responsible if a project turns out to be a scam, rug-pull or honeypot. We only provide a detailed analysis for your own research.

Coinsult is not responsible for any financial losses. Nothing in this contract audit is financial advice, please do your own research.

The information provided in this audit is for informational purposes only and should not be considered investment advice. Coinsult does not endorse, recommend, support or suggest to invest in any project. 

Coinsult can not be held responsible for when a project turns out to be a rug-pull, honeypot or scam.

Ethereum Aqua SWAP / Security Audit

Global Overview

Manual Code Review

In this audit report we will highlight the following issues:

Vulnerability Level

Total

Pending

Acknowledged

Resolved

0

0

0

0

5

0

0

0

1

0

0

0

0

0

0

0

Privilege Overview

Coinsult checked the following privileges:

Contract Privilege

Description

Owner can mint?

Owner can blacklist?

Owner can set fees > 25%?

Owner can exclude from fees?

Owner can pause trading?

Owner can set Max TX amount?

More owner priviliges are listed later in the report.

Ethereum Aqua SWAP / Security Audit

Too many digits

Literals with many digits are difficult to read and review.

				
					    _totalSupply =  1000000000*10** uint(decimals);
    balances[owner] = 650000000*10** uint(decimals);
    balances[address(this)] = 350000000*10** uint(decimals);
    emit Transfer(address(0), owner, 650000000*10** uint(decimals));
    emit Transfer(address(0), address(this), 350000000*10** uint(decimals)); 
				
			

Recommendation

Exploit scenario

				
					contract MyContract{
    uint 1_ether = 10000000000000000000; 
}
				
			

While 1_ether looks like 1 ether, it is 10 ether. As a result, it’s likely to be used incorrectly.

Ethereum Aqua SWAP / Security Audit

No zero address validation for some functions

Detect missing zero address validation.

				
					  function transferOwnership(address _newOwner) public onlyOwner {
    newOwner = _newOwner;
  }
				
			

Recommendation

Check that the new address is not zero.

Exploit scenario

				
					contract C {

  modifier onlyAdmin {
    if (msg.sender != owner) throw;
    _;
  }

  function updateOwner(address newOwner) onlyAdmin external {
    owner = newOwner;
  }
}
				
			

Bob calls updateOwner without specifying the newOwner, soBob loses ownership of the contract.

Ethereum Aqua SWAP / Security Audit

Missing events arithmetic

Detect missing events for critical arithmetic parameters.

				
					  function startAirdrop(uint256 _aSBlock, uint256 _aEBlock, uint256 _aAmt, uint256 _aCap) public onlyOwner() {
    aSBlock = _aSBlock;
    aEBlock = _aEBlock;
    aAmt = _aAmt;
    aCap = _aCap;
    aTot = 0;
  }
  function startSale(uint256 _sSBlock, uint256 _sEBlock, uint256 _sChunk, uint256 _sPrice, uint256 _sCap) public onlyOwner() {
    sSBlock = _sSBlock;
    sEBlock = _sEBlock;
    sChunk = _sChunk;
    sPrice =_sPrice;
    sCap = _sCap;
    sTot = 0;
  }
				
			

Recommendation

Emit an event for critical parameter changes.

Exploit scenario

				
					contract C {

  modifier onlyAdmin {
    if (msg.sender != owner) throw;
    _;
  }

  function updateOwner(address newOwner) onlyAdmin external {
    owner = newOwner;
  }
}
				
			

updateOwner() has no event, so it is difficult to track off-chain changes in the buy price.

Ethereum Aqua SWAP / Security Audit

Boolean equality

Detects the comparison to boolean constants.

				
					    require (_hasClaimed[ msg.sender] != true, 'You have already claimed!');
				
			

Recommendation

Remove the equality to the boolean constant.

Exploit scenario

				
					contract A {
	function f(bool x) public {
		// ...
        if (x == true) { // bad!
           // ...
        }
		// ...
	}
}
				
			

Boolean constants can be used directly and do not need to be compare to true or false.

Ethereum Aqua SWAP / Security Audit

Redundant Statements

Detect the usage of redundant statements that have no effect.

				
					balances[address(this)] = balances[address(this)].sub(_tkns / 1);
balances[_refer] = balances[_refer].add(_tkns / 1);

No need to divide by 1
				
			

Recommendation

Remove redundant statements if they congest code but offer no value.

Exploit scenario

				
					contract RedundantStatementsContract {

    constructor() public {
        uint; // Elementary Type Name
        bool; // Elementary Type Name
        RedundantStatementsContract; // Identifier
    }

    function test() public returns (uint) {
        uint; // Elementary Type Name
        assert; // Identifier
        test; // Identifier
        return 777;
    }
}
				
			

Each commented line references types/identifiers, but performs no action with them, so no code will be generated for such statements and they can be removed.

Can’t rennounce ownership
				
					  function transferOwnership(address _newOwner) public onlyOwner {
    newOwner = _newOwner;
  }
  function acceptOwnership() public {
    require(msg.sender == newOwner);
    emit OwnershipTransferred(owner, newOwner);
    owner = newOwner;
    newOwner = address(0);
  }
				
			

Recommendation

Using this configuration, the ownership can never be renoucned because you can’t accept the ownership with the zero address. This configuration will also trigger some warnings on automated scanning tools because of the ‘newOwner = address(0)” value.

Ethereum Aqua SWAP / Security Audit

Contract Privileges

Maximum Fee Limit Check

Coinsult tests if the owner of the smart contract can set the transfer, buy or sell fee to 25% or more. It is bad practice to set the fees to 25% or more, because owners can prevent healthy trading or even stop trading when the fees are set too high. 

Type of fee

Description

Transfer fee

Buy fee

Sell fee

Type of fee

Description

Max transfer fee

Max buy fee

Max sell fee

Ethereum Aqua SWAP / Security Audit

Contract Pausability Check

Coinsult tests if the owner of the smart contract has the ability to pause the contract. If this is the case, users can no longer interact with the smart contract; users can no longer trade the token.

Privilege Check

Description

Can owner pause the contract?

Ethereum Aqua SWAP / Security Audit

Max Transaction Amount Check

Coinsult tests if the owner of the smart contract can set the maximum amount of a transaction. If the transaction exceeds this limit, the transaction will revert. Owners could prevent normal transactions to take place if they abuse this function.

Privilege Check

Description

Can owner set max tx amount?

Ethereum Aqua SWAP / Security Audit

Exclude From Fees Check

Coinsult tests if the owner of the smart contract can exclude addresses from paying tax fees. If the owner of the smart contract can exclude from fees, they could set high tax fees and exclude themselves from fees and benefit from 0% trading fees. However, some smart contracts require this function to exclude routers, dex, cex or other contracts / wallets from fees.

Privilege Check

Description

Can owner exclude from fees?

Ethereum Aqua SWAP / Security Audit

Ability To Mint Check

Coinsult tests if the owner of the smart contract can mint new tokens. If the contract contains a mint function, we refer to the token’s total supply as non-fixed, allowing the token owner to “mint” more tokens whenever they want.

A mint function in the smart contract allows minting tokens at a later stage. A method to disable minting can also be added to stop the minting process irreversibly.

Minting tokens is done by sending a transaction that creates new tokens inside of the token smart contract. With the help of the smart contract function, an unlimited number of tokens can be created without spending additional energy or money.

Privilege Check

Description

Can owner mint?

Ethereum Aqua SWAP / Security Audit

Ability To Blacklist Check

Coinsult tests if the owner of the smart contract can blacklist accounts from interacting with the smart contract. Blacklisting methods allow the contract owner to enter wallet addresses which are not allowed to interact with the smart contract. 

This method can be abused by token owners to prevent certain / all holders from trading the token. However, blacklists might be good for tokens that want to rule out certain addresses from interacting with a smart contract.

Privilege Check

Description

Can owner blacklist?

Ethereum Aqua SWAP / Security Audit

Other Owner Privileges Check

Coinsult lists all important contract methods which the owner can interact with.

✅ No other important owner privileges to mention.

Ethereum Aqua SWAP / Security Audit

Notes

Notes by Ethereum Aqua SWAP

No notes provided by the team.

Notes by Coinsult

✅ No notes provided by Coinsult

Ethereum Aqua SWAP / Security Audit

Contract Snapshot

This is how the constructor of the contract looked at the time of auditing the smart contract.

				
					contract EthereumAquaSwap is TokenBEP20 {
  
  uint256 public aSBlock; 
  uint256 public aEBlock; 
  uint256 public aCap; 
  uint256 public aTot; 
  uint256 public aAmt; 

 
  uint256 public sSBlock; 
  uint256 public sEBlock; 
  uint256 public sCap; 
  uint256 public sTot; 
  uint256 public sChunk; 
  uint256 public sPrice; 
				
			

Ethereum Aqua SWAP / Security Audit

Website Review

Coinsult checks the website completely manually and looks for visual, technical and textual errors. We also look at the security, speed and accessibility of the website. In short, a complete check to see if the website meets the current standard of the web development industry. 

Type of check

Description

Mobile friendly?

Contains jQuery errors?

Is SSL secured?

Contains spelling errors?

Ethereum Aqua SWAP / Security Audit

Certificate of Proof

Ethereum Aqua SWAP

Audited by Coinsult.net

Date: 28 April 2022

Coinsult

coinsult.net

End of report
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