Let's start another challenge from Nebula machine and see what's our target this time.
Finally, exams are over so it's time to get back to security topics. Today I'm going to start documenting journey through Nebula machine from Exploit Exercises.
A little break in the exams, so we have some time to discover another topic - which is file permissions on Linux. Let's fully understand how they work.
Frequency analysis is the study of the frequency of letters or groups of letters occuring next to each other. The most ancient description for what we know was made by Al-Kindi, dating back to the IXth century. This attack is used to break monoalphabetic ciphers, which work by simple and fixed substitution of letters. We now, that if the a in plaintext is encrypted to x letter, everytime in the ciphertext that x will convert to a.