Smart contract bugs can lose millions in minutes. Audit your code and understand the most common attack vectors.
Smart contract security is critical — bugs are permanent and exploits are public.
Top vulnerabilities:
1. Reentrancy — re-enter a function before state updates. Fix: Checks-Effects-Interactions, ReentrancyGuard.
2. Integer overflow/underflow — use Solidity >=0.8 (auto-checked) or SafeMath.
3. Access control — missing onlyOwner checks. Use OpenZeppelin AccessControl.
4. tx.origin — use msg.sender for auth.
5. Front-running — MEV bots read mempool. Use commit-reveal scheme or private mempools.
6. Oracle manipulation — use TWAPs, multiple oracles, Chainlink.
7. Signature replay — include chainId, nonce, contract address in signed messages.
8. Self-destruct & force-feeding ETH — don't rely on address(this).balance.
9. Delegatecall storage collisions — careful with proxy patterns.
10. Denial of Service — avoid unbounded loops, pull-over-push.
Tools:
- Slither — static analysis
- Mythril — symbolic execution
- Echidna / Foundry — fuzz testing
- OpenZeppelin Defender — monitoring & automation
Top vulnerabilities:
1. Reentrancy — re-enter a function before state updates. Fix: Checks-Effects-Interactions, ReentrancyGuard.
2. Integer overflow/underflow — use Solidity >=0.8 (auto-checked) or SafeMath.
3. Access control — missing onlyOwner checks. Use OpenZeppelin AccessControl.
4. tx.origin — use msg.sender for auth.
5. Front-running — MEV bots read mempool. Use commit-reveal scheme or private mempools.
6. Oracle manipulation — use TWAPs, multiple oracles, Chainlink.
7. Signature replay — include chainId, nonce, contract address in signed messages.
8. Self-destruct & force-feeding ETH — don't rely on address(this).balance.
9. Delegatecall storage collisions — careful with proxy patterns.
10. Denial of Service — avoid unbounded loops, pull-over-push.
Tools:
- Slither — static analysis
- Mythril — symbolic execution
- Echidna / Foundry — fuzz testing
- OpenZeppelin Defender — monitoring & automation