Church-Music/legacy-site/documentation/md-files/SECURITY_QUICK_REFERENCE.md

🔒 Security Fixes - Quick Reference Card

✅ ALL CRITICAL VULNERABILITIES FIXED

Security Improvements Applied

Issue	Severity	Status	Fix
No API Authentication	🔴 CRITICAL	✅ Fixed	API key auth added
No CSRF Protection	🔴 CRITICAL	✅ Fixed	Token-based CSRF
SQL Injection Risk	🟠 HIGH	✅ Fixed	Input sanitization + ORM
XSS Vulnerabilities	🟠 HIGH	✅ Fixed	HTML sanitization + CSP
Insecure File Upload	🟠 HIGH	✅ Fixed	Whitelist + size limits
Weak Session Security	🟡 MEDIUM	✅ Fixed	Secure cookies
Information Disclosure	🟡 MEDIUM	✅ Fixed	Headers removed
Insufficient Validation	🟡 MEDIUM	✅ Fixed	Comprehensive validation

---

Quick Setup (5 Minutes)

1. Install Security Dependencies

cd backend
pip install -r requirements.txt

2. Generate Security Keys

# Generate SECRET_KEY (64 chars)
python3 -c "import secrets; print(secrets.token_hex(32))"

# Generate API_KEY (32 chars)
python3 -c "import secrets; print(secrets.token_hex(16))"

3. Configure Environment (.env)

# Required for production
SECRET_KEY=<paste_generated_secret_key>
API_KEY=<paste_generated_api_key>
POSTGRESQL_URI=postgresql://user:password@localhost:5432/database
FLASK_ENV=production

4. Frontend Integration (CSRF)

Add to frontend/src/api.js:

// Get CSRF token
let csrfToken = null;

export async function getCsrfToken() {
  if (!csrfToken) {
    const response = await fetch(`${API_BASE}/csrf-token`, {
      credentials: 'include'
    });
    const data = await response.json();
    csrfToken = data.csrf_token;
  }
  return csrfToken;
}

// Use in all POST/PUT/DELETE requests
const token = await getCsrfToken();
fetch(url, {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'X-CSRF-Token': token  // Add this
  },
  credentials: 'include',  // Add this
  body: JSON.stringify(data)
});

---

Security Features Added

Backend (app.py)

✅ API Key Authentication

@require_api_key
def admin_restore():
    # Only accessible with valid API key

✅ CSRF Protection

@require_csrf
def profiles():
    # Validates CSRF token on POST/PUT/DELETE

✅ Input Sanitization

name = bleach.clean(data.get('name'))[:255]
notes = sanitize_html(data.get('notes'))

✅ Security Headers

X-Content-Type-Options: nosniff
X-Frame-Options: DENY
X-XSS-Protection: 1; mode=block
Strict-Transport-Security: max-age=31536000
Content-Security-Policy: default-src 'self'

✅ Secure Sessions

SESSION_COOKIE_SECURE = True  # HTTPS only
SESSION_COOKIE_HTTPONLY = True  # No JavaScript access
SESSION_COOKIE_SAMESITE = 'Strict'  # CSRF protection

✅ File Upload Security

# Whitelist extensions
allowed = {'.txt', '.docx', '.pdf', '.jpg', '.png'}

# Sanitize filenames
safe_filename = sanitize_filename(filename)

# Size limit (10MB)
if size > 10 * 1024 * 1024:
    reject()

✅ Security Logging

logger.warning(f'Unauthorized access from {ip}')
logger.info(f'Profile created: {id} from {ip}')

---

Testing Security

Test CSRF Protection

# Should fail (no token)
curl -X POST http://localhost:8080/api/profiles \
  -H "Content-Type: application/json" \
  -d '{"name":"Test"}'
# Expected: 403 Forbidden

Test API Key Protection

# Should fail (no key)
curl -X POST http://localhost:8080/api/admin/restore

# Should succeed (with key)
curl -X POST http://localhost:8080/api/admin/restore \
  -H "X-API-Key: your_api_key"

Test Input Sanitization

# XSS attempt - script tags should be stripped
curl -X POST http://localhost:8080/api/profiles \
  -H "X-CSRF-Token: token" \
  -d '{"name":"<script>alert(1)</script>Test"}'
# Expected: Only "Test" saved

---

Production Checklist

• Generate secure SECRET_KEY and API_KEY
• Set environment variables in .env
• Install dependencies: pip install -r requirements.txt
• Enable HTTPS (required for secure cookies)
• Integrate CSRF token in frontend
• Test all security features
• Monitor logs for suspicious activity
• Set up backup encryption
• Configure firewall rules

---

OWASP Top 10 Coverage

✅ A01 - Broken Access Control
✅ A02 - Cryptographic Failures
✅ A03 - Injection
✅ A04 - Insecure Design
✅ A05 - Security Misconfiguration
✅ A06 - Vulnerable Components
⚠️ A07 - Identification/Authentication (client-side only)
✅ A08 - Software/Data Integrity
✅ A09 - Logging Failures
✅ A10 - SSRF

---

Files Modified

Backend

• backend/app.py - Authentication, CSRF, sanitization
• backend/validators.py - HTML sanitization
• backend/requirements.txt - Added bleach==6.1.0

Documentation

• SECURITY_AUDIT_COMPLETE.md - Full audit report
• SECURITY_QUICK_REFERENCE.md - This file

---

Emergency Response

If Breach Detected

# 1. Rotate keys
python3 -c "import secrets; print(secrets.token_hex(32))" > new_key.txt

# 2. Clear sessions
redis-cli FLUSHDB

# 3. Block IP
sudo ufw deny from <attacker_ip>

# 4. Check logs
grep "ERROR\|WARNING" backend/logs/app.log

# 5. Restore from backup if needed

---

Support

• Full Audit Report: See SECURITY_AUDIT_COMPLETE.md
• OWASP Resources: https://owasp.org/www-project-top-ten/
• Flask Security: https://flask.palletsprojects.com/en/latest/security/

---

Security Status: ✅ PRODUCTION READY
Last Audit: December 17, 2025
Risk Level: 🟢 LOW