Potential for Protocol Surplus Due to Indivisible atomDepositFractionOnTripleCreation

[hats-bug-reporter]

Github username: --
Twitter username: --
Submission hash (on-chain): 0x45af594e37907786efc19eea5046d4b897518936ba6dc1ee0e011e4b1bfa26dd
Severity: low

Description:
Description
In the setAtomDepositFractionOnTripleCreation function of the EthMultiVault contract, there's no check to ensure that the atomDepositFractionOnTripleCreation value is divisible by 3. This could lead to a small amount of ETH being left in the protocol when creating triples, as the value is meant to be equally distributed among three atoms.

Attack Scenario\

While not a direct security vulnerability, this oversight can lead to the following issues:

1. Small amounts of ETH could accumulate in the protocol over time due to rounding errors.
2. The actual distribution of ETH to the three atoms in a triple may be slightly uneven.
3. Over a large number of transactions, this could result in a noticeable discrepancy between expected and actual ETH distribution.

Attachments

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "./EthMultiVault.sol";

contract EthMultiVaultFractionTest {
    EthMultiVault public vault;

    constructor(address _vaultAddress) {
        vault = EthMultiVault(_vaultAddress);
    }

    function testFractionDivisibility(uint256 newFraction) external {
        // Assume this contract has admin rights
        vault.setAtomDepositFractionOnTripleCreation(newFraction);
        
        uint256 setFraction = vault.tripleConfig().atomDepositFractionOnTripleCreation;
        uint256 remainder = setFraction % 3;
        
        require(remainder == 0, "Fraction not perfectly divisible by 3");
    }
}

2. Revised Code File (Optional)

function setAtomDepositFractionOnTripleCreation(uint256 atomDepositFractionOnTripleCreation) external onlyAdmin {
    // Ensure the value is divisible by 3
    uint256 adjustedFraction = (atomDepositFractionOnTripleCreation / 3) * 3;
    
    tripleConfig.atomDepositFractionOnTripleCreation = adjustedFraction;

    emit AtomDepositFractionUpdated(adjustedFraction);
}

[mihailo-maksa]

The report highlights that there is no check to ensure atomDepositFractionOnTripleCreation is divisible by 3, potentially leading to small amounts of ETH being left in the protocol.

Label: invalid

Comment:
Since the value of atomDepositFractionOnTripleCreation is fixed and can only be set by the admin, we do not consider this a security vulnerability. At best, it can be considered a low-priority enhancement, primarily since the accumulated difference will be so negligible that it doesn’t have any practical impact. No fix is needed if the value divisible by 3 is used in the deploy script.