# Security Checklist

**Date**: 2026-01-24  
**Status**: Pre-Audit Security Review

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## 🔒 **Security Review Checklist**

### **1. Access Control** ✅

- [x] All admin functions protected with `onlyRole(DEFAULT_ADMIN_ROLE)`
- [x] Critical functions use role-based access control
- [x] Role assignments are properly restricted
- [x] No public functions that modify critical state
- [ ] Review role escalation vectors
- [ ] Verify role revocation works correctly

### **2. Reentrancy Protection** ✅

- [x] `ReentrancyGuard` used in bridge contracts
- [x] `nonReentrant` modifier on critical functions
- [x] Checks-Effects-Interactions pattern followed
- [ ] Review all external calls for reentrancy risks
- [ ] Test reentrancy attack scenarios

### **3. Integer Overflow/Underflow** ✅

- [x] Solidity 0.8.20+ (built-in overflow protection)
- [x] SafeMath not needed (compiler handles it)
- [ ] Review arithmetic operations for edge cases
- [ ] Test with maximum values

### **4. Input Validation** ✅

- [x] Zero address checks
- [x] Amount validation (non-zero, within limits)
- [x] Destination validation in adapters
- [ ] Review all user inputs
- [ ] Test with invalid inputs

### **5. Upgrade Safety** ✅

- [x] UUPS proxy pattern used
- [x] `_authorizeUpgrade` protected
- [x] Storage layout compatibility maintained
- [ ] Review upgrade paths
- [ ] Test upgrade scenarios

### **6. Oracle Security** ⚠️

- [x] Multiple price feeds for XAU Oracle
- [x] Staleness checks implemented
- [x] Quorum requirements for Reserve Oracle
- [ ] Review oracle manipulation risks
- [ ] Test oracle failure scenarios
- [ ] Implement circuit breakers

### **7. Bridge Security** ⚠️

- [x] Request ID generation uses nonces
- [x] Status tracking prevents double execution
- [x] Cancellation mechanism implemented
- [ ] Review cross-chain message validation
- [ ] Test message replay attacks
- [ ] Verify CCIP message authentication

### **8. Token Security** ✅

- [x] ERC20 standard compliance
- [x] Transfer restrictions enforced
- [x] Mint/burn controls implemented
- [ ] Review token approval risks
- [ ] Test token transfer edge cases

### **9. Vault Security** ⚠️

- [x] Health ratio checks before operations
- [x] Liquidation protection
- [x] Debt ceiling enforcement
- [ ] Review liquidation mechanics
- [ ] Test undercollateralized scenarios
- [ ] Verify interest accrual accuracy

### **10. Compliance & Regulatory** ✅

- [x] KYC checks in ISO-4217W system
- [x] Reserve verification
- [x] Jurisdiction restrictions
- [ ] Review compliance logic
- [ ] Test compliance bypass attempts

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## 🛡️ **Security Best Practices**

### **Code Quality**
- [x] Use latest Solidity version (0.8.20)
- [x] Follow OpenZeppelin patterns
- [x] Comprehensive error messages
- [ ] Code review completed
- [ ] Documentation complete

### **Testing**
- [x] Unit tests for core functions
- [x] Integration tests
- [ ] Fuzz testing
- [ ] Formal verification (if applicable)
- [ ] Test coverage > 80%

### **Monitoring**
- [ ] Event logging for critical operations
- [ ] Admin alerts for unusual activity
- [ ] Bridge monitoring dashboard
- [ ] Oracle health checks

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## 🚨 **Known Risks & Mitigations**

### **High Risk**

1. **Oracle Manipulation**
   - **Risk**: Single oracle failure or manipulation
   - **Mitigation**: Multiple price feeds, quorum requirements, staleness checks
   - **Status**: ⚠️ Needs review

2. **Bridge Message Replay**
   - **Risk**: Replay of cross-chain messages
   - **Mitigation**: Request IDs, nonces, status tracking
   - **Status**: ⚠️ Needs testing

3. **Liquidation Attacks**
   - **Risk**: Front-running liquidation transactions
   - **Mitigation**: MEV protection, fair liquidation
   - **Status**: ⚠️ Needs review

### **Medium Risk**

1. **Upgrade Risks**
   - **Risk**: Storage collision during upgrades
   - **Mitigation**: UUPS pattern, storage layout checks
   - **Status**: ✅ Implemented

2. **Access Control**
   - **Risk**: Role escalation or unauthorized access
   - **Mitigation**: Role-based access control, multi-sig
   - **Status**: ✅ Implemented

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## 📋 **Pre-Audit Preparation**

### **Required Documentation**
- [x] Architecture documentation
- [x] Contract specifications
- [x] Deployment procedures
- [ ] Threat model
- [ ] Risk assessment

### **Test Coverage**
- [x] Unit tests
- [x] Integration tests
- [ ] Fuzz tests
- [ ] Formal verification

### **Code Review**
- [x] Internal code review
- [ ] External security review
- [ ] Audit scheduled

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## ✅ **Security Audit Readiness**

**Status**: ⚠️ **In Progress**

**Completed**:
- ✅ Access control implementation
- ✅ Reentrancy protection
- ✅ Input validation
- ✅ Upgrade safety

**Pending**:
- ⏳ Comprehensive security audit
- ⏳ Fuzz testing
- ⏳ Formal verification
- ⏳ External code review

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**Next Steps**:
1. Complete fuzz testing
2. Schedule security audit
3. Address audit findings
4. Deploy to testnet
5. Monitor and iterate