caxton 0.1.4

A secure WebAssembly runtime for multi-agent systems
Documentation
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# Security Audit Checklist

## Overview
This comprehensive security audit checklist ensures Caxton maintains robust security posture across all components, from WebAssembly sandboxing to API authentication and resource protection.

## Audit Categories

1. **WebAssembly Sandbox Security**
2. **API Authentication & Authorization**
3. **Resource Exhaustion Protection**
4. **Data Security & Privacy**
5. **Network Security**
6. **Operational Security**
7. **Compliance & Governance**

---

## 1. WebAssembly Sandbox Security

### Isolation Verification
- [ ] **Memory Isolation**
  - [ ] Verify linear memory bounds checking
  - [ ] Confirm no shared memory between agents
  - [ ] Test memory growth limits enforcement
  - [ ] Validate stack overflow protection

- [ ] **Capability Restrictions**
  - [ ] No filesystem access outside sandbox
  - [ ] No network access without explicit permission
  - [ ] No system call access
  - [ ] No process spawning capability

- [ ] **Resource Limits**
  - [ ] CPU time limits enforced
  - [ ] Memory limits enforced (default: 100MB)
  - [ ] Stack size limits enforced
  - [ ] Instruction count limits (gas metering)

### WASM Module Verification
```rust
// Audit code example
pub fn verify_wasm_module(module: &[u8]) -> SecurityAuditResult {
    let mut results = SecurityAuditResult::new();

    // Check for dangerous imports
    let dangerous_imports = [
        "fs", "process", "child_process", "net", "dgram"
    ];

    for import in parse_imports(module) {
        if dangerous_imports.contains(&import.module) {
            results.add_violation(
                Severity::Critical,
                format!("Dangerous import detected: {}", import.module)
            );
        }
    }

    // Verify memory configuration
    if let Some(memory) = parse_memory_section(module) {
        if memory.initial > MAX_INITIAL_MEMORY {
            results.add_violation(
                Severity::High,
                "Excessive initial memory allocation"
            );
        }
    }

    results
}
```

### Sandbox Escape Testing
- [ ] **Known CVE Testing**
  - [ ] Test against known WebAssembly CVEs
  - [ ] Verify patches for Spectre/Meltdown
  - [ ] Test bounds checking bypass attempts

- [ ] **Fuzzing**
  - [ ] Fuzz WASM module loader
  - [ ] Fuzz host function interfaces
  - [ ] Fuzz memory operations

- [ ] **Resource Exhaustion**
  - [ ] Test infinite loop handling
  - [ ] Test memory bomb prevention
  - [ ] Test stack overflow handling

## 2. API Authentication & Authorization

### Authentication Mechanisms
- [ ] **API Key Management**
  - [ ] Keys stored securely (never in code)
  - [ ] Key rotation implemented
  - [ ] Key revocation functional
  - [ ] Rate limiting per key

- [ ] **JWT/Token Validation**
  - [ ] Signature verification
  - [ ] Expiration checking
  - [ ] Audience validation
  - [ ] Issuer verification

- [ ] **mTLS Implementation**
  - [ ] Certificate validation
  - [ ] Certificate revocation checking
  - [ ] Proper cipher suite selection
  - [ ] TLS version >= 1.2

### Authorization Controls
```yaml
# Authorization matrix audit
authorization_matrix:
  admin:
    - agent:create
    - agent:delete
    - agent:modify
    - system:configure

  operator:
    - agent:create
    - agent:read
    - metrics:read

  viewer:
    - agent:read
    - metrics:read
```

- [ ] **RBAC Implementation**
  - [ ] Role definitions documented
  - [ ] Least privilege principle enforced
  - [ ] Role assignment audited
  - [ ] Permission inheritance correct

- [ ] **API Endpoint Security**
  - [ ] All endpoints require authentication
  - [ ] Sensitive operations require additional auth
  - [ ] CORS properly configured
  - [ ] CSRF protection enabled

### Security Headers
```rust
// Required security headers
pub const SECURITY_HEADERS: &[(&str, &str)] = &[
    ("X-Content-Type-Options", "nosniff"),
    ("X-Frame-Options", "DENY"),
    ("X-XSS-Protection", "1; mode=block"),
    ("Strict-Transport-Security", "max-age=31536000; includeSubDomains"),
    ("Content-Security-Policy", "default-src 'self'"),
    ("Referrer-Policy", "strict-origin-when-cross-origin"),
];
```

## 3. Resource Exhaustion Protection

### Rate Limiting
- [ ] **Request Rate Limiting**
  - [ ] Per-IP rate limiting
  - [ ] Per-user rate limiting
  - [ ] Per-endpoint rate limiting
  - [ ] Distributed rate limiting (Redis)

- [ ] **Resource Quotas**
  - [ ] Max agents per user
  - [ ] Max messages per second
  - [ ] Max storage per user
  - [ ] Max CPU time per agent

### DoS Protection
```rust
// DoS protection configuration
pub struct DosProtection {
    max_connections: usize,           // 10000
    max_connections_per_ip: usize,    // 100
    max_request_size: usize,           // 10MB
    max_header_size: usize,            // 8KB
    request_timeout: Duration,         // 30s
    slow_request_threshold: Duration,  // 10s
}
```

- [ ] **Connection Limits**
  - [ ] Max concurrent connections enforced
  - [ ] Connection timeout configured
  - [ ] Slow loris protection
  - [ ] SYN flood protection

- [ ] **Request Validation**
  - [ ] Max request size enforced
  - [ ] Max header size enforced
  - [ ] Request timeout enforced
  - [ ] Body parsing limits

## 4. Data Security & Privacy

### Encryption
- [ ] **Data at Rest**
  - [ ] Database encryption enabled
  - [ ] File system encryption
  - [ ] Backup encryption
  - [ ] Key management system (KMS) integrated

- [ ] **Data in Transit**
  - [ ] TLS for all external communication
  - [ ] TLS for internal services
  - [ ] Certificate pinning where appropriate
  - [ ] Perfect forward secrecy enabled

### Sensitive Data Handling
```rust
// Sensitive data detection
pub fn audit_sensitive_data(data: &str) -> Vec<SensitiveDataMatch> {
    let patterns = [
        (r"\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b", "email"),
        (r"\b(?:\d{4}[-\s]?){3}\d{4}\b", "credit_card"),
        (r"\b\d{3}-\d{2}-\d{4}\b", "ssn"),
        (r"(?i)(api[_-]?key|secret|password|token)[\s]*[:=][\s]*['\"]?[\w-]+", "credential"),
    ];

    let mut matches = Vec::new();
    for (pattern, data_type) in patterns {
        // Check for matches and record
    }
    matches
}
```

- [ ] **PII Protection**
  - [ ] PII identification automated
  - [ ] PII encryption enforced
  - [ ] PII access logged
  - [ ] PII retention policies enforced

- [ ] **Secrets Management**
  - [ ] No hardcoded secrets
  - [ ] Environment variables used properly
  - [ ] Secrets rotation implemented
  - [ ] Audit trail for secret access

### GDPR Compliance
- [ ] **Data Subject Rights**
  - [ ] Right to access implemented
  - [ ] Right to deletion implemented
  - [ ] Right to portability implemented
  - [ ] Consent management system

- [ ] **Data Processing**
  - [ ] Lawful basis documented
  - [ ] Data minimization enforced
  - [ ] Purpose limitation enforced
  - [ ] Data retention automated

## 5. Network Security

### Network Segmentation
```yaml
# Network zones
network_zones:
  dmz:
    - load_balancer
    - api_gateway

  application:
    - orchestrator
    - agent_runtime

  data:
    - database
    - message_queue

  management:
    - monitoring
    - logging
```

- [ ] **Zone Isolation**
  - [ ] Firewall rules configured
  - [ ] Network ACLs in place
  - [ ] Security groups properly configured
  - [ ] Private subnets for internal services

- [ ] **Traffic Control**
  - [ ] Ingress rules minimized
  - [ ] Egress filtering enabled
  - [ ] Inter-zone communication restricted
  - [ ] VPN for management access

### Communication Security
- [ ] **Service Mesh Security**
  - [ ] mTLS between services
  - [ ] Service authentication
  - [ ] Traffic encryption
  - [ ] Circuit breakers configured

- [ ] **Message Queue Security**
  - [ ] Queue authentication required
  - [ ] Message encryption
  - [ ] Access control lists
  - [ ] Dead letter queue monitoring

## 6. Operational Security

### Logging and Monitoring
```rust
// Security event logging
pub enum SecurityEvent {
    AuthenticationFailure { user: String, ip: IpAddr },
    AuthorizationFailure { user: String, resource: String },
    SuspiciousActivity { description: String },
    SecurityPolicyViolation { policy: String, violator: String },
    DataExfiltrationAttempt { user: String, volume: usize },
}

impl SecurityEvent {
    pub fn log(&self) {
        match self {
            SecurityEvent::AuthenticationFailure { .. } => {
                // Log with appropriate severity and details
            }
            // ... other cases
        }
    }
}
```

- [ ] **Security Logging**
  - [ ] Authentication events logged
  - [ ] Authorization failures logged
  - [ ] Configuration changes logged
  - [ ] Data access logged

- [ ] **Log Security**
  - [ ] Logs encrypted in transit
  - [ ] Logs encrypted at rest
  - [ ] Log tampering detection
  - [ ] Log retention policies enforced

### Incident Response
- [ ] **Incident Response Plan**
  - [ ] Response team identified
  - [ ] Escalation procedures documented
  - [ ] Communication plan established
  - [ ] Recovery procedures tested

- [ ] **Security Monitoring**
  - [ ] Real-time threat detection
  - [ ] Anomaly detection configured
  - [ ] Alert fatigue minimized
  - [ ] 24/7 monitoring (if required)

### Patch Management
- [ ] **Vulnerability Management**
  - [ ] Regular vulnerability scanning
  - [ ] Dependency scanning automated
  - [ ] CVE monitoring active
  - [ ] Patch testing procedures

- [ ] **Update Procedures**
  - [ ] Security update SLA defined
  - [ ] Emergency patch process
  - [ ] Rollback procedures tested
  - [ ] Change management integrated

## 7. Compliance & Governance

### Security Policies
- [ ] **Documentation**
  - [ ] Security policy documented
  - [ ] Acceptable use policy
  - [ ] Data classification policy
  - [ ] Incident response policy

- [ ] **Training & Awareness**
  - [ ] Security training program
  - [ ] Phishing awareness training
  - [ ] Secure coding training
  - [ ] Regular security updates

### Compliance Frameworks
```yaml
# Compliance mapping
compliance_requirements:
  SOC2:
    - access_control
    - encryption
    - monitoring
    - incident_response

  ISO27001:
    - risk_assessment
    - asset_management
    - access_control
    - cryptography

  PCI_DSS:
    - network_security
    - access_control
    - regular_testing
    - security_policies
```

- [ ] **Regulatory Compliance**
  - [ ] GDPR requirements met
  - [ ] CCPA requirements met
  - [ ] Industry-specific regulations
  - [ ] Data residency requirements

- [ ] **Audit Trail**
  - [ ] Complete audit logging
  - [ ] Audit log integrity
  - [ ] Regular audit reviews
  - [ ] External audit readiness

## Security Testing Procedures

### Penetration Testing
```bash
# Automated security testing
#!/bin/bash

# OWASP ZAP scan
docker run -t owasp/zap2docker-stable zap-baseline.py \
  -t https://caxton.example.com \
  -r security-report.html

# Nmap service discovery
nmap -sV -sC -O -p- target.example.com

# SQLMap for injection testing
sqlmap -u "https://api.example.com/agents?id=1" \
  --batch --random-agent

# Nikto web scanner
nikto -h https://caxton.example.com
```

### Security Scanning
- [ ] **Static Analysis (SAST)**
  - [ ] Code scanning enabled
  - [ ] Secret scanning enabled
  - [ ] Dependency scanning enabled
  - [ ] License compliance scanning

- [ ] **Dynamic Analysis (DAST)**
  - [ ] API security testing
  - [ ] Web application scanning
  - [ ] Container scanning
  - [ ] Infrastructure scanning

### Security Metrics
```rust
pub struct SecurityMetrics {
    pub vulnerabilities_open: u32,
    pub mean_time_to_remediate: Duration,
    pub security_incidents: u32,
    pub false_positive_rate: f64,
    pub coverage_percentage: f64,
}

impl SecurityMetrics {
    pub fn calculate_risk_score(&self) -> f64 {
        // Risk scoring algorithm
    }
}
```

## Remediation Priority Matrix

| Finding Severity | Exposure | Timeline | Action |
|-----------------|----------|----------|---------|
| Critical | External | 24 hours | Emergency patch |
| Critical | Internal | 48 hours | Urgent fix |
| High | External | 1 week | Priority fix |
| High | Internal | 2 weeks | Scheduled fix |
| Medium | Any | 30 days | Normal fix |
| Low | Any | 90 days | Backlog |

## Security Review Schedule

### Daily
- Monitor security alerts
- Review authentication failures
- Check resource usage anomalies

### Weekly
- Review access logs
- Update threat intelligence
- Patch assessment

### Monthly
- Security metrics review
- Vulnerability scan
- Access review
- Certificate expiration check

### Quarterly
- Penetration testing
- Security training
- Policy review
- Compliance audit

### Annually
- Full security audit
- Disaster recovery test
- Security architecture review
- Third-party assessment

## References
- [ADR-0002: WebAssembly for Agent Isolation]../adr/0002-webassembly-for-agent-isolation.md
- [OWASP Top 10]https://owasp.org/www-project-top-ten/
- [NIST Cybersecurity Framework]https://www.nist.gov/cyberframework
- [CIS Controls]https://www.cisecurity.org/controls