Python OWASP Top Ten — ELI5

Think of your web app as a house. You’ve built it, painted it, moved in your furniture. But you forgot to check the doors and windows. The OWASP Top Ten is a checklist of the ten most common ways burglars break into houses — except the houses are websites, and the burglars are hackers.

OWASP is a nonprofit that studies how web apps get hacked. Every few years, they publish a list of the ten most dangerous and common vulnerabilities. Developers who fix these ten things stop the vast majority of real-world attacks.

Here’s the idea in everyday terms:

1. Broken access control — Someone opens a page they shouldn’t see, like walking into the manager’s office because the door was unlocked.
2. Bad cryptography — Storing passwords in plain text, like writing your PIN on the back of your debit card.
3. Injection — A hacker types special commands into a form, and the app accidentally runs them.
4. Insecure design — The app was never designed to be safe, like a house with no locks on the blueprints.
5. Misconfiguration — Leaving default passwords or debug mode turned on in production.
6. Outdated components — Using old libraries with known security holes.
7. Authentication failures — Weak login systems that let attackers guess passwords or steal sessions.
8. Data integrity failures — Trusting data or updates without verifying they haven’t been tampered with.
9. Logging failures — Not recording what happened, so you can’t tell when or how you were breached.
10. Server-side request forgery — Tricking the server into fetching internal resources on the attacker’s behalf.

Python frameworks like Django and Flask have built-in protections for many of these. But the protections only work if you know they exist and actually use them.

The one thing to remember: the OWASP Top Ten is the fire safety code for web apps — it won’t prevent every possible fire, but ignoring it guarantees you’ll get burned.