MaxiMine Token (MXM) security audit, conducted by the Callisto Network Security Department in July 2019.

 

MaxiMine (MXM) Specificities

 

 

 

Audit Request

Audit Top 200 CoinMarketCap tokens.

Maximine Coin (MXM).

https://maximine.io/

Source Code:

https://etherscan.io/address/0x8e766f57f7d16ca50b4a0b90b88f6468a09b0439#code

Disclosure policy:

Public.

Platform:

ETH.

Number of lines:

88.

 

MaxiMine (MXM) Smart Contract Security Audit Report

Are Your Funds Safe?

 

1. In scope

2. Findings

In total, 5 issues were reported including:

  • 4 low severity issues.
  • 1 owner privilege (the ability of an owner to manipulate contract, may be risky for investors).

No critical security issues were found.

2.1. Known vulnerabilities of ERC-20 token

Severity: low.

Description:

  1. It is possible to double withdrawal attack. More details here.

  2. Lack of transaction handling mechanism issue. WARNING! This is a very common issue and it already caused millions of dollars losses for lots of token users! More details here.

Recommendation:

Add the following code to the transfer(_to address, ...) function:

require( _to != address(this) );

2.2. ERC20 Compliance — event missing

Severity: low.

Description:

According to ERC20 standard when coins are minted(or burned) a Transfer event should be emitted.

Code snippet:

  • Line 41, 163, 181.

2.3. ERC20 Compliance — transfer returns

Severity: low.

Description:

According EIP20 Standard the transfer function should returns boolean value function transfer(address _to, uint256 _value) public returns (bool success). But here it is not implemented.

Code snippet.

  • Line 76.

2.4. ERC20 Compliance: zero-value transfers rejecting

Severity: low.

Description:

EIP20 says that:

Transfers of 0 values MUST be treated as normal transfers and fire the Transfer event.
But in this contract, function transfer has a condition:

require(balanceOf[_to] + _value > balanceOf[_to]);

Code snippet:

  • Line 56.

2.5. Owner Privileges

Severity: owner privileges.

Description:

The contract owner allowed to ban transfer functions for certain user.

Code snippet:

  • Line 86, 77, 111, 128.

3. Conclusion

The audited smart contract can be deployed. Only low severity issues were found during the audit.

4. Revealing audit reports

Appendix

Smart Contract Audits by Callisto Network.

Miscellaneous

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