HEXA Staking - Smart Contract Audit Report


HEXA Staking Audit Report HEXA is building a new staking platform that allows users to deposit ETH and earn rewards in HEXA tokens.

We audited the project team's HEXAStaking contract using code provided by the project team.

Notes on the Contract:
  • The HEXAStaking contract is used to facilitate multiple staking rounds in which users can deposit ETH into the contract and receive rewards in HEXA tokens in return.
  • The owner must initialize the contract in order to allow deposits and withdrawals.
  • Users can only deposit one time in an active staking round.
  • Each round is broken down into a set of periods that can have differing rewards rates.
  • On withdrawals, unpaid rewards are transferred from the HEXA Allowance address to the user.
  • The project team must ensure the HEXA Allowance address has enough HEXA tokens to support the reward distributions, and that the proper approvals are in place to allow the HEXA tokens to be transferred.
  • The HEXA token contract was not included in the scope of this audit, so we are unable to provide an assessment of this contract with regards to security.
  • Rewards are calculated based on the time staked, the reward rate in the latest qualifying period, and the ETH to HEXA ratio set by the team; Users will not qualify for any rewards at all if withdrawing before the first period begins.
  • Users can withdraw their funds staked in previous rounds at any time. Rewards for previous rounds do not accrue after the round has finished.
  • The owner can start a new round at any time, as long as there is not a round currently running.
  • The owner can end an ongoing round at any time.
  • The owner can only set the reward rates and the periods for the next round only, as long as there is not a round currently running.
  • The owner can set the ETH to HEXA ratio for reward distributions to any value, as long as there is not a round currently running.
  • The team has worked with us to optimize this contract for gas efficiency.
  • As the contract is implemented with Solidity v0.8.x, it is protected from overflows.
  • The contract utilizes ReentrancyGuard to prevent re-entrancy attacks in applicable functions.

Audit Findings Summary
  • No security threats from outside attackers were identified.
  • Ensure trust in the team prior to investing as they have substantial control in the ecosystem.
  • Date: November 7th, 2021
  • Updated: November 8th, 2021 to address an issue with withdrawing.
Resolved Issues
  • The team addressed an issue within the contract that allowed users to withdraw more staked funds and rewards than were due.

External Threat Results

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
External CallsN/APASS
Integer Over/UnderflowN/APASS
Multiple SendsN/APASS
State Change External CallsN/APass
Unchecked RetvalN/APASS
User Supplied AssertionN/APASS
Critical Solidity CompilerN/APASS
Overall Contract Safety PASS

HEXAStaking Contract

BEP20 Token Graph

Multi-file Token

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

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

 +  Ownable (Context)
    - [Pub]  #
    - [Pub] owner
    - [Pub] renounceOwnership #
       - modifiers: onlyOwner
    - [Pub] transferOwnership #
       - modifiers: onlyOwner
    - [Int] _transferOwnership #

 +  ReentrancyGuard 
    - [Pub]  #

 + [Int] IERC20 
    - [Ext] transferFrom #
    - [Ext] allowance #

 +  HEXAStaking (ReentrancyGuard, Ownable)
    - [Pub]  #
    - [Ext] initialize #
       - modifiers: onlyOwner
    - [Pub] deposit ($)
       - modifiers: initialized,isRunning,reentrancyGuard
    - [Ext]  ($)
    - [Ext] withdraw #
       - modifiers: initialized,isRunning,reentrancyGuard
    - [Int] _withdraw #
    - [Int] getCurrentReward
    - [Pub] withdrawableHoldings
    - [Pub] legacyWithdraw #
       - modifiers: reentrancyGuard
    - [Int] _withdrawableHoldings
    - [Int] _getStakePeriod
    - [Pub] getCurrentStakeAmount
    - [Pub] getCurrentStakeTimestamp
    - [Ext] startRound #
       - modifiers: onlyOwner,notRunning
    - [Ext] endRound #
       - modifiers: onlyOwner,isRunning
    - [Ext] setRewards #
       - modifiers: onlyOwner,notRunning
    - [Ext] setRatio #
       - modifiers: onlyOwner,notRunning