name: smart-contract-security
description: Master smart contract security with auditing, vulnerability detection, and incident response
sasmp_version: "1.3.0"
version: "2.0.0"
updated: "2025-01"
bonded_agent: 06-smart-contract-security
bond_type: PRIMARY_BOND

Skill Configuration

atomic: true
single_responsibility: security_auditing

Parameter Validation

parameters:
topic:
type: string
required: true
enum: [vulnerabilities, auditing, tools, incidents]
severity:
type: string
default: all
enum: [critical, high, medium, low, all]

Retry & Error Handling

retry_config:
max_attempts: 3
backoff: exponential
initial_delay_ms: 1000

Logging & Observability

logging:
level: info
include_timestamps: true
track_usage: true

Smart Contract Security Skill

Master smart contract security with vulnerability detection, auditing methodology, and incident response procedures.

Quick Start

# Invoke this skill for security analysis
Skill("smart-contract-security", topic="vulnerabilities", severity="high")

Topics Covered

1. Common Vulnerabilities

Recognize and prevent:
- Reentrancy: CEI pattern violation
- Access Control: Missing modifiers
- Oracle Manipulation: Flash loan attacks
- Integer Issues: Precision loss

2. Auditing Methodology

Systematic review process:
- Manual Review: Line-by-line analysis
- Static Analysis: Automated tools
- Fuzzing: Property-based testing
- Formal Verification: Mathematical proofs

3. Security Tools

Essential tooling:
- Slither: Fast static analysis
- Mythril: Symbolic execution
- Foundry: Fuzzing, invariants
- Certora: Formal verification

4. Incident Response

Handle security events:
- Triage: Assess severity
- Mitigation: Emergency actions
- Post-mortem: Root cause analysis
- Disclosure: Responsible reporting

Vulnerability Quick Reference

Critical: Reentrancy

// VULNERABLE
function withdraw(uint256 amount) external {
    (bool ok,) = msg.sender.call{value: amount}("");
    require(ok);
    balances[msg.sender] -= amount;  // After call!
}

// FIXED: CEI Pattern
function withdraw(uint256 amount) external {
    balances[msg.sender] -= amount;  // Before call
    (bool ok,) = msg.sender.call{value: amount}("");
    require(ok);
}

High: Missing Access Control

// VULNERABLE
function setAdmin(address newAdmin) external {
    admin = newAdmin;  // Anyone can call!
}

// FIXED
function setAdmin(address newAdmin) external onlyOwner {
    admin = newAdmin;
}

High: Unchecked Return Value

// VULNERABLE
IERC20(token).transfer(to, amount);  // Ignored!

// FIXED: Use SafeERC20
using SafeERC20 for IERC20;
IERC20(token).safeTransfer(to, amount);

Medium: Precision Loss

// VULNERABLE: Division before multiplication
uint256 fee = (amount / 1000) * rate;

// FIXED: Multiply first
uint256 fee = (amount * rate) / 1000;

Audit Checklist

Pre-Audit

• [ ] Code compiles without warnings
• [ ] Tests pass with good coverage
• [ ] Documentation reviewed

Core Security

• [ ] CEI pattern followed
• [ ] Reentrancy guards present
• [ ] Access control on admin functions
• [ ] Input validation complete

DeFi Specific

• [ ] Oracle staleness checks
• [ ] Slippage protection
• [ ] Flash loan resistance
• [ ] Sandwich prevention

Security Tools

Static Analysis

# Slither - Fast vulnerability detection
slither . --exclude-dependencies

# Mythril - Symbolic execution
myth analyze src/Contract.sol

# Semgrep - Custom rules
semgrep --config "p/smart-contracts" .

Fuzzing

// Foundry fuzz test
function testFuzz_Withdraw(uint256 amount) public {
    amount = bound(amount, 1, type(uint128).max);

    vm.deal(address(vault), amount);
    vault.deposit{value: amount}();

    uint256 before = address(this).balance;
    vault.withdraw(amount);

    assertEq(address(this).balance, before + amount);
}

Invariant Testing

function invariant_BalancesMatchTotalSupply() public {
    uint256 sum = 0;
    for (uint i = 0; i < actors.length; i++) {
        sum += token.balanceOf(actors[i]);
    }
    assertEq(token.totalSupply(), sum);
}

Severity Classification

Incident Response

1. Detection

# Monitor for suspicious activity
cast logs --address $CONTRACT --from-block latest

2. Mitigation

// Emergency pause
function pause() external onlyOwner {
    _pause();
}

3. Recovery

• Assess damage scope
• Coordinate disclosure
• Deploy fixes with audit

Common Pitfalls

Cross-References

• Bonded Agent: 06-smart-contract-security
• Related Skills: solidity-development, defi-protocols

Resources

• SWC Registry: Common weakness enumeration
• Rekt News: Hack post-mortems
• Immunefi: Bug bounties

Version History