kienbui1995/blockchain-audit

Blockchain & Smart Contract Audit

When to Use

When reviewing Solidity/Rust smart contracts before deployment, preparing for a formal security audit, or assessing web3 integration risks.

Core Jobs

1. Smart Contract Security Checklist

Critical vulnerabilities to check:

• [ ] Reentrancy: Does state update before external call? Use CEI pattern (Checks-Effects-Interactions)
• [ ] Integer overflow/underflow: Using SafeMath or Solidity 0.8+?
• [ ] Access control: Are admin functions properly restricted? (onlyOwner, role-based)
• [ ] Front-running: Can transaction ordering be exploited? (price oracle manipulation)
• [ ] Unchecked return values: Are all .call() return values checked?
• [ ] Timestamp dependence: Is block.timestamp used for randomness or time-sensitive logic?
• [ ] Denial of service: Can loops be made to run out of gas?
• [ ] Logic errors: Does the business logic match the spec exactly?

2. DeFi-Specific Risks

• Flash loan attacks: Can an attacker manipulate price oracles in a single transaction?
• Price oracle manipulation: Using on-chain DEX prices without TWAP?
• Slippage: Are swap functions protected against excessive slippage?
• Liquidity: Are there constraints on withdrawal that could trap funds?

3. Code Quality Review

• Test coverage: 100% line coverage expected for mainnet contracts
• Static analysis: run Slither, MythX, or Semgrep on contract code
• Fuzzing: Echidna or Foundry fuzz tests for edge cases
• Formal verification: for critical financial logic

4. Pre-Audit Checklist

• [ ] All known issues resolved or documented
• [ ] Test coverage > 95%
• [ ] Static analysis clean (no medium+ findings)
• [ ] Deployment scripts reviewed
• [ ] Emergency pause mechanism exists
• [ ] Upgrade mechanism reviewed (proxy pattern risks)

Key Outputs

• Security findings report (severity: Critical / High / Medium / Low / Info)
• Pre-audit readiness assessment
• Remediation recommendations
• Post-fix verification

Anti-Patterns

• Deploying to mainnet without audit
• "We'll fix it in the next version" for critical vulnerabilities (immutable contracts)
• Trusting on-chain data without validation
• No emergency mechanism — can't pause a compromised contract