Before we move on to the challenges, I would like to tell you all that this room is not for absolute beginner or person who doesn’t know anything in cyber security domain.
It includes various cryptographic techniques to be used along with some stego and stegenoghaphy challenges. This may sound new but it will be fun learning it.
This is only for the reference purpose and i would request you to go through the challenge before reading this write-up. You can go through the challenge here : CTF
What is CTF or capture the flag ?
CTF is a gamified learning techniques used in cyber security domain. In this game a flag in form of encrypted text is hidden and we need to find the plain text in-order to get the answer. We can use several tools and techniques in order to get the flag. It is also hosted as a competition now a days, where 2 or more teams compete with each other. So now we got some knowledge about what is CTF, let’s get back to the challenge !
Task -1 Translation & Shifting
This task requires you to perform a translation or shifting in certain ciphers such as ROT13, ROT47, Morse code, etc.
It is so simple. Just see the text carefully. It is in Leet form. So basically a Leet is a form of font which is used mostly on the internet. Is a famous font used by numerous hackers. For example, leet spellings of the word leet include 1337 and l33t; eleet may be spelled 31337 or 3l33t. Now you could find it east to guess the answer !
Answer : can you capture the flag.
Here ‘a’ was replaced by ‘4’, ‘o’ by ‘0’, ‘t’ by ‘7’, ‘r’ by ‘2’, ‘e’ by ‘3’ and so on…
You can also use this tool to solve this : tool
This format seems to be a Binary number . So Binary numbers include1’s and 0’s which is the only language a computer or machine understands. For this we will be using an online Tool “CyberChef”. We will convert it from Binary to Plain Text. You can also use this tool named “RapidTables”. After conversion you will get the answer to the question.
Answer : lets try some binary out!
This format seems to be Base 32 . Base32 is a common transfer encoding. It consists of 32-char set. These char-sets are usually alphabet in uppercase.So again we will use “CyberChef”. We will convert it from Base 32 to Plain Text. So your CyberChef window will look something similar to this one !
Answer : base32 is super common in CTF’s
This Format seems to be Base 64. Base64 is another common transfer encoding. It consists of 64-char set. These char-sets are usually alphabet in uppercase and lowercase. We are gonna use “CyberChef” again. We will convert it From Base 64 to Plain Text.
Answer : Each Base64 digit represents exactly 6 bits of data.
This format seems to be Hex. Hex or we generally say it hexadecimal consists of 16 bits of binary. It also known as base16. We will convert it from Hex to Plain Text.
Answer : hexadecimal or base16?
This format seems to be ROT 13. There is some hint given in the text .Rot 13 or known as rotate 13 is a form of Caesar cipher which rotate in 13 times. We will convert it From ROT 13 to Plain Text .
Answer : Rotate me 13 places!
This format seems to be ROT 47. Rot 47 or known as rotate 47 is another form of Caesar cipher which rotate in 47 times. It encode almost all visible ASCII character. We will convert it From ROT 47 to Plain Text.
Answer : You spin me right round baby right round (47 times)
This seems to be some Telecommunication Encrypted Message. This is Morse code. Morse code is a combination of signal made of short and long impulsion (dot and dash). It was designed for telecommunication .We will convert it from Morse code to Plain Text.
Answer : TELECOMMUNICATION ENCODING
This seems to be some Binary-Coded Decimal Text. Binary-Coded Decimal (BCD) is a base10 encoding technique.We will convert it from decimal to Plain Text.
Answer : Unpack this BCD
This seems to be very long text . It is As Mentioned Below :-
This can not be solved with the help of only one technique, for this we need to apply several layered technique to find the plain text. As we can see there is “=” sign at the end of the text, why not to try From Base64 .
technique 1 > From Base 64
So now from the result we can assume that this may be Morse code.
technique 2 > Morse code
Now in result we can see so many 1’s and 0’s, so it will be definitely a binary numbers.
technique 3 > Binary Number
Now it seems to be something tricky but wait… we have seen something like this before, where all the ASCII characters are being used. Okay so it will be ROT47.
technique 4 > ROT47
Now it seems we have seen this type of number before… guess what ! you are right it’s Binary coded decimal. So we will convert this from Decimal.
technique 5 > From Decimal
Horray ! We have solved this tricky encryption.
Answer : Let’s make this a bit trickier…
Remember that you won’t be getting direct cipher text as we have seen from question number 1–9, what you will be getting in real time CTS’s would be something similar to question no 10.
Congratulations ! You have completed Task 1. See you soon, till then