5 Layers of Security: How TopFlow Mitigates OWASP Top 10
As a former CISO, I don't just talk about security—I implement it. Here's TopFlow's 5-layer defense-in-depth model and how it addresses every OWASP Top 10 vulnerability.
Security as a Showcase Priority
As a former CISO, I built TopFlow not just as a functional AI workflow builder, but as a demonstration of production-grade security architecture. Every line of code reflects 15 years of security leadership experience.
This blog post is aimed at hiring managers, VCs, and security professionals evaluating technical talent. I want to show that I don't just understand security theory—I implement it at every layer.
The 5-Layer Security Model
TopFlow uses a defense-in-depth approach with five distinct security layers. Each layer addresses specific threats, and together they provide comprehensive protection:
Layer 1: Client-Side
Input sanitization, XSS prevention, CSP headers
Layer 2: Transport
TLS 1.3, HSTS, secure headers
Layer 3: API Gateway
Rate limiting, DDoS protection, authentication
Layer 4: Execution
SSRF prevention, cycle detection, timeout enforcement
Layer 5: External APIs
HTTPS-only, user credentials, API validation
OWASP Top 10 Coverage
Here's how TopFlow addresses each of the OWASP Top 10 vulnerabilities with specific implementation details:
A01: Injection
Risk: SQL injection, command injection, XSS attacks
Mitigation:
- Zod schemas validate all user inputs
- DOMPurify sanitizes HTML content
- No direct database queries (stateless architecture)
- React auto-escapes JSX by default
import { z } from 'zod'
import DOMPurify from 'dompurify'
const NodeSchema = z.object({
id: z.string().uuid(),
type: z.enum(['llm', 'http', 'transform']),
config: z.record(z.string(), z.any()),
})
// Sanitize user-provided HTML
const clean = DOMPurify.sanitize(userInput)A03: Sensitive Data Exposure
Risk: PII leakage, API key exposure, data breaches
Mitigation:
- No PII storage (privacy-first architecture)
- API keys stored client-side only (localStorage)
- TLS 1.3 for all connections
- HSTS headers enforce HTTPS
A05: Security Misconfiguration
Risk: Exposed endpoints, verbose errors, default credentials
Mitigation:
- Security headers (CSP, X-Frame-Options, X-Content-Type-Options)
- Error messages don't leak stack traces in production
- No default credentials (BYOK model)
- Regular npm audit and Snyk scanning
A10: Server-Side Request Forgery (SSRF)
Risk: Internal network access, cloud metadata exposure
Mitigation:
- HTTPS-only URL validation
- Private IP blocking (10.x, 172.16.x, 192.168.x, 169.254.x)
- Cloud metadata endpoint blocking
- Allowlist approach for external APIs
Production-Grade Controls
Beyond OWASP, TopFlow implements additional security controls:
- Rate Limiting: 10 requests/minute per IP using Redis-backed distributed counters
- Timeout Enforcement: 30-second maximum execution time prevents resource exhaustion
- Cycle Detection: Graph analysis prevents infinite loops in workflows
- Input Validation: Zod schemas enforce type safety and constraints
Conclusion
Building secure applications isn't about adding security as an afterthought—it's about designing security into every layer from the start. TopFlow demonstrates that former CISOs can still code, and that security expertise translates directly into better architecture decisions.
Want to see these security controls in action? Try building a workflow at topflow.dev.