Governance - Onyx DAO

1. Introduction

Onyx engaged Halborn to conduct a security assessment on their smart contracts beginning on February 12th, 2025 and ending on February 21th, 2025. The security assessment was scoped to the smart contracts provided to Halborn. Commit hashes and further details can be found in the Scope section of this report.

The Onyx codebase in scope consist of 4 different solidity files:

• MasterChef contract: Its purpose is to distribute rewards to stakers based on their stake.

• CHNGovernance contract: It allows users to create proposals and vote on them.

• CHNTimelock contract: It is responsible for queuing and executing proposals from the CHNGovernance contract.

• CHNStaking contract: It enables users to stake tokens, rewards them based on their stakes, and tracks their voting power.

2. Assessment Summary

Halborn was provided 8 days for the engagement and assigned 1 full-time security engineer to review the security of the smart contracts in scope. The engineer is a blockchain and smart contract security expert with advanced smart contract hacking skills, and deep knowledge of multiple blockchain protocols.

The purpose of the assessment is to:

• Identify potential security issues within the smart contracts.

• Ensure that smart contract functionality operates as intended.

In summary, Halborn identified some improvements to reduce the likelihood and impact of risks, which should be addressed by the Onyx team. The main ones were the following:

• Consider enforcing the maxXcnPerSecond parameter in the constructor, or remove it entirely.

• Consider using multisig wallet address for the guardian address. Additionally consider adding functionality to change the guardian address in the CHNGovernance contract.

• Consider adding the proposal id into the calculation of the operation id in the _queueOrRevert() function.

• Consider caching the length of the proposal.targets array before you loop over them.

3. Test Approach and Methodology

Halborn performed a combination of manual review of the code and automated security testing to balance efficiency, timeliness, and accuracy in regard to the scope of this assessment. While manual testing is recommended to uncover flaws in logic, process, and implementation; automated testing techniques help enhance coverage of smart contracts and can quickly identify items that do not follow security best practices.

The following phases and associated tools were used throughout the term of the assessment:

• Research into architecture, purpose and use of the platform.

• Smart contract manual code review and walkthrough to identify any logic issue.

• Thorough assessment of safety and usage of critical Solidity variables and functions in scope that could lead to arithmetic related vulnerabilities.

• Local testing with custom scripts (Foundry).

• Fork testing against main networks (Foundry).

• Static analysis of security for scoped contract, and imported functions(Slither).