🐸 From Froga

Tech

Capture the flag

The rooms that go with the capture-the-flag labs: codes and ciphers, digital forensics, phishing, then the web. Play a warm-up before its lab, and the rest alongside it.

9 rooms

1
Before you break codes
The maths behind the Crypto lab, without the heavy parts: bytes and hex, XOR, remainders, and why multiplying two primes is easy but splitting the answer is hard. Ten minutes.
8 blocks · by Froga
2
Symmetric Encryption & Classical Ciphers
From Caesar's shift cipher to AES: what a cipher and a key actually are, why classical ciphers fall to frequency analysis, and why modern block ciphers replaced DES.
10 blocks · by Froga
3
Asymmetric Encryption & Digital Signatures
Why public-key cryptography needs two keys, which one does what, and how running the pair backwards turns encryption into a signature.
8 blocks · by Froga
4
Before you investigate
The ideas the Digital Forensics lab assumes: what a file signature is, what base64 does, how metadata hides in plain sight, and what a log line actually says. Ten minutes.
8 blocks · by Froga
5
Before you open that email
The ideas the Spot the Phish lab assumes: display names versus real addresses, lookalike domains, what SPF/DKIM/DMARC actually check, and what to do instead of clicking. Ten minutes.
8 blocks · by Froga
6
Spot the Phish: Email Red Flags at Work
A short security-awareness check for any office team — the signals that give a phishing email away, the myths that get people caught, and what to do when something looks wrong.
7 blocks · by Froga
7
Email Security: SPF, DKIM and DMARC
Why a protocol with no authentication at all needed three bolted on afterwards — what each of the three actually checks, and which address a human reader is looking at.
7 blocks · by Froga
8
Before Web Security 1
The ideas the Web security lab assumes: how a request and response work, what a URL’s parts are, what a cookie is, and the one that makes everything after it possible — the browser fills in the request, so the request is yours to change. About ten minutes.
8 blocks · by Froga
9
Before Web Security 2
The ideas the Web security 2 lab assumes: what a signed token is, how a database query is built from parts, why a server fetching a URL for you is different from you fetching it, and the theme under all of it — the server must not trust data just because it handled it. About ten minutes.
8 blocks · by Froga