Specialty · Security Free to read

Cyber Security Basics tutorial

Think like a defender: passwords, injection, tokens, logs and firewalls, each tried out in real code.

9 lessonsabout 12 h Learn first: Python from Zero

Learn it by doing

The interactive course has the same lessons with an editor next to them: run every example, answer the quizzes and solve exercises that are checked the moment you submit. Free to start, no sign-up.

Start the interactive course

Think like a defender

What to protect, and why encoding is not encryption.

1 Threats and riskWhat are we protecting, and from what?2 Encoding and encryptionIs Base64 encryption? What actually keeps a message secret?

Passwords

Store passwords safely and see how guessing works.

3 Hashing and saltIf the user database leaks, can attackers read everyone's password?4 Brute force in numbersHow long would it take to guess a password?

Web attacks

Stop input from becoming code.

5 SQL injectionHow can typing into a login box give someone admin access?6 XSS and path traversalHow can a comment box run code in other people's browsers?

Detect and defend

Signed tokens, log analysis and firewall rules.

7 Tokens and HMACHow does a server know a cookie wasn't changed by the user?8 Finding attacks in logsSomeone is guessing passwords on our server. How do we find them in the logs?9 Firewall rulesHow does a firewall decide which traffic gets in?