Capture the Flag (CTF) Crypto Challenges
"Each crypto flag found is proof that your mind can turn chaos into clarity."
What are crypto ctf challenges ?
As you know cryptography has a major role in cyber security for securing confidentiality, integrity and non-repudation of data. In almost all ctf comptitions you will get a category "Crypto" or "Cryptography".
Challenges in this category test your different encoding, encryption, custom algrithm recognization and solving skills. You have to use your creative mind, maths, logics to solve these problesms.
These challenges are similer to the realworld cryptography weaknesses and vulnerabilities.
How challenges looks like ?
In crypto challenges you will generally get a encoded/encrypted string or a file having these value in it. In CTF compititions generally a hint remains hidden in the name of challenge or in description. Sometime you can get the actual code that is used to translate the original value.
How to solve a crypto ctf challenge ?
To solve a crypto ctf challenge, first you have to identify the encryption/encoding technique, or custom pattern that is used to change the original value (flag). Generally you can find these techniques in challenge name/descritotion itself as a hint. Or a code may be given, which is used to change the original flag.
You your skills to solve the technique and retrive the original value.
Generally the flag uses following format => xyz{String_or_l33t_or_random_word} where xyz is generally the short name of ctf organizer
Where to practice cryptography challenges ?
Below some plateforms are listed where you can do practicle learning to solve cryptography challanges. I also wrote some writeups of solutions, if you get stuck in solving any challage you can use my writeups as reference.
Common tools for crypto ctf solving :
The more you practice, new trick and techniques you will get to know and take less time to solve any challange.