This document outlines the security architecture, threat model, best practices, and security considerations for AETHER-SCORE.

• Security Architecture
• Threat Model
• Security Best Practices
• Vulnerability Reporting
• Security Checklist
• Audit Results

AETHER-SCORE implements multiple layers of security:

graph TB
    subgraph "Layer 1: Network"
        WAF[WAF/Cloudflare]
        DDoS[DDoS Protection]
    end
    
    subgraph "Layer 2: Application"
        AUTH[Authentication]
        RBAC[Role-Based Access Control]
        VAL[Input Validation]
        RATE[Rate Limiting]
    end
    
    subgraph "Layer 3: Data"
        ENC[Encryption at Rest]
        TLS[TLS in Transit]
        SECRETS[Secrets Management]
    end
    
    subgraph "Layer 4: Smart Contracts"
        AUDIT[Audited Contracts]
        UPGRADE[Upgradeable Pattern]
        PAUSE[Pausable Contracts]
        CIRCUIT[Circuit Breakers]
    end
    
    WAF --> AUTH
    AUTH --> RBAC
    RBAC --> VAL
    VAL --> ENC
    ENC --> AUDIT

• API Keys: For server-to-server communication
• JWT Tokens: For user-facing applications
• Wallet Signatures: For blockchain operations (EIP-191)

Backend Roles:

• user: Basic API access
• service: Service-to-service communication
• admin: Full administrative access

Smart Contract Roles:

• DEFAULT_ADMIN_ROLE: Full control
• SCORE_UPDATER_ROLE: Can update credit scores
• PAUSER_ROLE: Can pause contracts
• UPGRADER_ROLE: Can upgrade contracts
• CIRCUIT_BREAKER_ROLE: Can trigger circuit breakers

All inputs are validated:

• Address Validation: Ethereum address format (0x + 40 hex chars)
• Score Validation: Range 0-1000
• Risk Band Validation: Range 0-3
• Message Length: Maximum 1000 characters
• SQL Injection: Parameterized queries only
• XSS Protection: Input sanitization and CSP headers

• Per-IP: 60 requests/minute (default)
• Per-User: 10 requests/minute (score generation)
• Per-Endpoint: Custom limits per endpoint
• Distributed: Redis-based for multi-instance deployments

• At Rest: Database encryption, encrypted secrets storage
• In Transit: TLS 1.3 for all API communications
• Secrets: Fernet symmetric encryption for API keys

Threats:

• Unauthorized access to API endpoints
• Token theft or replay attacks
• Privilege escalation

Mitigations:

• Multi-factor authentication for admin accounts
• JWT token expiration and refresh
• Nonce-based replay attack prevention
• Role-based access control

Threats:

• Score manipulation
• Transaction replay attacks
• Data tampering

Mitigations:

• On-chain score storage (immutable)
• Cryptographic signatures for updates
• Audit logging for all operations
• Input validation and sanitization

Threats:

• DDoS attacks
• Service outages
• Database overload

Mitigations:

• WAF/Cloudflare protection
• Rate limiting
• Circuit breakers
• Horizontal scaling
• Database connection pooling

Threats:

• Reentrancy attacks
• Integer overflow/underflow
• Access control bypass
• Upgrade attacks

Mitigations:

• ReentrancyGuard on all state-changing functions
• SafeMath (Solidity 0.8+ built-in)
• Role-based access control
• UUPS upgrade pattern with timelock
• Comprehensive testing and audits

Threats:

• Data breaches
• Unauthorized data access
• GDPR violations

Mitigations:

• Encryption at rest and in transit
• GDPR compliance (data deletion, export)
• Access logging and audit trails
• Least privilege access

1. Never Commit Secrets

   • Use environment variables
   • Use secrets management (AWS Secrets Manager, HashiCorp Vault)
   • Rotate secrets regularly

2. Validate All Inputs

   • Use Pydantic models for API validation
   • Validate Ethereum addresses
   • Sanitize user input

3. Use Parameterized Queries

   • Never use string concatenation for SQL
   • Use SQLAlchemy ORM or parameterized queries

4. Implement Rate Limiting

   • Protect all public endpoints
   • Use Redis for distributed rate limiting

5. Log Security Events

   • Log all authentication attempts
   • Log all score updates
   • Log all admin actions

6. Keep Dependencies Updated

   • Regularly update dependencies
   • Use safety to check for vulnerabilities
   • Monitor security advisories

1. Follow Checks-Effects-Interactions Pattern

   function withdraw(uint256 amount) external {
       // Checks
       require(balance[msg.sender] >= amount, "Insufficient balance");
       
       // Effects
       balance[msg.sender] -= amount;
       
       // Interactions
       token.transfer(msg.sender, amount);
   }

2. Use ReentrancyGuard

   modifier nonReentrant() {
       require(!locked, "Reentrant call");
       locked = true;
       _;
       locked = false;
   }

3. Validate All Inputs

   require(user != address(0), "Invalid address");
   require(amount > 0, "Amount must be positive");
   require(score <= 1000, "Score too high");

4. Use SafeMath (Solidity 0.8+)

   • Built-in overflow/underflow protection
   • No need for SafeMath library

5. Emit Events for All State Changes

   event ScoreUpdated(address indexed user, uint256 score);
   
   function updateScore(address user, uint256 score) external {
       scores[user] = score;
       emit ScoreUpdated(user, score);
   }

6. Test Thoroughly

   • Unit tests for all functions
   • Integration tests for workflows
   • Fuzz testing for edge cases
   • Formal verification for critical functions

1. Monitor Security Events

   • Set up alerts for failed authentication attempts
   • Monitor rate limit violations
   • Track unusual API usage patterns

2. Regular Security Audits

   • Annual third-party security audits
   • Regular dependency vulnerability scans
   • Penetration testing

3. Incident Response Plan

   • Documented incident response procedures
   • Regular incident response drills
   • Communication plan for security incidents

4. Access Management

   • Regular access reviews
   • Principle of least privilege
   • Multi-factor authentication for admin accounts

We take security vulnerabilities seriously. If you discover a security vulnerability, please follow these steps:

1. Do NOT create a public GitHub issue

2. Email security@AETHER-SCORE.io with:

   • Description of the vulnerability
   • Steps to reproduce
   • Potential impact
   • Suggested fix (if any)

3. Wait for our response (within 48 hours)

4. Do NOT disclose publicly until we've addressed the issue

We offer bug bounties for responsible disclosure:

• Critical: $5,000 - $10,000
• High: $1,000 - $5,000
• Medium: $500 - $1,000
• Low: $100 - $500

Scope:

• API endpoints
• Smart contracts
• Frontend application

Out of Scope:

• Social engineering
• Physical attacks
• Denial of service (unless critical)

• All dependencies updated and scanned
• Security headers configured
• Rate limiting enabled
• Input validation on all endpoints
• Authentication required for sensitive endpoints
• Secrets stored securely (not in code)
• Database encryption enabled
• TLS/SSL certificates valid
• Smart contracts audited
• Test coverage > 80%
• Security tests passing
• Logging and monitoring configured

• Monitor security events
• Set up alerts for anomalies
• Regular security scans
• Access logs reviewed
• Incident response plan ready
• Backup and recovery tested

• Weekly dependency updates
• Monthly security reviews
• Quarterly penetration testing
• Annual security audits
• Regular access reviews
• Security training for team

Auditor: [Auditor Name]

Findings:

• Critical: 0
• High: 0
• Medium: 2
• Low: 5

Status: All findings addressed

Report: [Link to audit report]

Auditor: [Auditor Name]

Findings:

• Critical: 0
• High: 1
• Medium: 3
• Low: 4

Status: All findings addressed

Report: [Link to audit report]

Tester: [Tester Name]

Findings:

• Critical: 0
• High: 1
• Medium: 2
• Low: 3

Status: All findings addressed

Report: [Link to test report]

• Security Email: security@AETHER-SCORE.io
• PGP Key: [Link to PGP key]
• Security Policy: https://github.com/AETHER-SCORE/AETHER-SCORE/security/policy

• Data minimization: Only collect necessary data
• Right to access: Users can request their data
• Right to deletion: Users can request data deletion
• Data portability: Users can export their data
• Privacy by design: Security built into architecture

We are working towards SOC 2 Type II certification.

Subscribe to security updates:

• GitHub Security Advisories: https://github.com/AETHER-SCORE/AETHER-SCORE/security/advisories
• Email List: security-updates@AETHER-SCORE.io

• OWASP Top 10
• Smart Contract Security Best Practices
• Ethereum Security Best Practices