The Complete SaaS Security Checklist for 2025

Security breaches cost SaaS companies an average of $4.24M per incident. Here's our battle-tested security checklist from protecting 50+ production applications.

Authentication & Authorization

Must-Have Features

• ✓ Password hashing with bcrypt (minimum 12 rounds)
• ✓ Multi-factor authentication (MFA) via TOTP or SMS
• ✓ OAuth 2.0 for third-party integrations
• ✓ Role-based access control (RBAC)
• ✓ Session management with secure tokens (JWT)
• ✓ Account lockout after failed login attempts
• ✓ Password reset with time-limited tokens

Implementation Example

// Secure password hashing
const hashedPassword = await bcrypt.hash(password, 12);

// JWT with short expiration
const token = jwt.sign(
  { userId, role },
  process.env.JWT_SECRET,
  { expiresIn: '15m' }
);

Data Protection

Encryption Requirements

• In Transit: TLS 1.3 minimum (no TLS 1.0/1.1)
• At Rest: AES-256 encryption for sensitive data
• Database: Encrypted backups and snapshots
• File Storage: S3 with server-side encryption

PII Handling

• Never log sensitive data (passwords, SSN, credit cards)
• Implement data masking in non-prod environments
• Use tokenization for payment information
• Automatic PII redaction in error logs

Application Security

OWASP Top 10 Protection

Security Headers

// Essential security headers
Strict-Transport-Security: max-age=31536000
X-Frame-Options: DENY
X-Content-Type-Options: nosniff
Content-Security-Policy: default-src 'self'
Referrer-Policy: strict-origin-when-cross-origin

Infrastructure Security

Cloud Security

• VPC isolation for database and backend services
• Security groups with least privilege access
• Automated security patching
• DDoS protection (CloudFlare, AWS Shield)
• Web Application Firewall (WAF)

Monitoring & Logging

• Centralized logging (CloudWatch, Datadog)
• Real-time security alerts
• Failed authentication tracking
• API rate limiting and abuse detection
• Audit logs for sensitive operations

Compliance Requirements

GDPR (EU)

• Data processing agreements (DPA)
• Right to access and deletion
• Cookie consent management
• Data breach notification (72 hours)
• Privacy policy and terms of service

SOC 2 Type II

• Security policies and procedures
• Access controls and monitoring
• Incident response plan
• Vendor risk assessment
• Annual penetration testing

Incident Response