Tryhackme C4ptur3-th3-fl4g Walthrough

1.Introduction#

This writeup is about challenge C4ptur3-th3-fl4g in Tryhackme Platform . In this writeup I am going to explain how the challenge/Tasks can be solved.

2.Transalation and Shifting#

The First task of this challenge can be solved by decoding the chipers such as ROT₁₃ , Base64 , Base32 , Morse code and binary. In this challenge all the Answers are Case Sensitive.

Task 1#

The task 1 Cipher is known l337 code. which be solved by simpling guessing it or using any online converters

Cipher : c4n y0u c4p7u23 7h3 f149?

Answer : can you capture the flag?

Task 2#

In this Task the Cipher is an binary code, which can either be solved using an Online Converter

Cipher :

1
                        01101100 01100101 01110100 01110011 00100000
2
                        01110100 01110010 01111001 00100000 01110011
3
                        01101111 01101101 01100101 00100000 01100010
4
                        01101001 01101110 01100001 01110010 01111001
5
                        00100000 01101111 01110101 01110100 00100001

Answer : lets try some binary out!

Task 3#

The 3rd Task is to deal with the Cipher base32. An base32 is numeral system of base 32. which uses set 32 digits .with 26 upper-case letter A-Z and the digits range from 2-7.

This challenge can solved using an online converter or using the command line

Cipher : MJQXGZJTGIQGS4ZAON2XAZLSEBRW63LNN5XCA2LOEBBVIRRHOM======

Command :

1
  echo "MJQXGZJTGIQGS4ZAON2XAZLSEBRW63LNN5XCA2LOEBBVIRRHOM======" | base32 -d

base32 decode

Answer : base32 is super common in CTF’s

Task 4#

In this we can see base64 chipher which realy common in almost all CTF challenges This can be also decoded using any online base64 decoder or using Command Line

Cipher :

RWFjaCBCYXNlNjQgZGlnaXQgcmVwcmVzZW50cyBleGFjdGx5IDYgYml0cyBvZiBkYXRhLg==

Command :

1
echo "RWFjaCBCYXNlNjQgZGlnaXQgcmVwcmVzZW50cyBleGFjdGx5IDYgYml0cyBvZiBkYXRhLg==" | base64 -d

base64 decode

Answer : Each Base64 digit represents exactly 6 bits of data.

Task 5#

Here the Cipher is an Hexadecimal , An hex is also known as base16 which consits of 16 bit binary.

We can also use the Online Converter this converter to solve the challenge or using xxd command to convert it to ascii form.

Cipher : 68 65 78 61 64 65 63 69 6d 61 6c 20 6f 72 20 62 61 73 65 31 36 3f

Command :

1
echo -e 68 65 78 61 64 65 63 69 6d 61 6c 20 6f 72 20 62 61 73 65 31 36 3f | xxd -r -p

hex decode using xxd Answer : hexadecimal or base16?

Task 6#

The Task is to convert an ROT₁₃ Cipher to ascii. in Rot13 each letter on a phrase is “rotated” 13 times.

An online converter is available to convert this rot13 cipher. or can use the command

Cipher : Ebgngr zr 13 cynprf!

Command :

1
  echo "Ebgngr zr 13 cynprf!" | tr '[A-Za-z]' '[N-ZA-Mn-za-m]'

Rot13 Decode

Answer : Rotate me 13 places!

Task 7#

The rot47 is also known as rotate 47. where the all the letters are rotated in 47 times it is also like the cipher ro13 but this contain all the characters in ascii including digits and Punctuations

we can use Rot47 online decoder to solve this challenge

Cipher : *@F DA:? >6 C:89E C@F?5 323J C:89E C@F?5 Wcf E:>6DX

Rot47 Online Decode

Answer : You spin me right round baby right round (47 times)

Task 8#

This task is to deal with Morse Code. with dashes and dotes

we can solve it using this morsecodedecoder

Cipher : - . .-.. . -.-. --- — — ..- -. .. -.-. .- - .. --- -. . -. -.-. --- -.. .. -. —.

Morse code decode

Answer : TELECOMMUNICATIONENCODING

Task 9#

Here we can see a BCD known Binary Coded Decimal . In an BCD each number represent it binary value. which is further converted to ascii to get series of letter.

Here i used an Online Converter Cryptii to solve this one

Cipher : 85 110 112 97 99 107 32 116 104 105 115 32 66 67 68

BCD Decode using cryptii

Answer : Unpack this BCD

Task 10#

This is the last task of Transalation and Shifting in this challenge . This task is the combination of all the above task that we done . which is a super cool but is little trickier.

It is an base64 encoded . To get the Answer First

Decode this base64

Then a morse code is obtained.
Decode that Morse Code

An binary code will obtain
Decode that Binary Code to ascii

we get ROT₄₇
Decode the Rot₄₇

An Decimal value will obtain
Decode this Decimal Value to Ascii to obtain the Final Answer

Answer : Let’s make this a bit trickier…

2. Spectrograms#

In this challenge Phase we have to deal with something called Spectrograms .

A spectrogram is a visual representation of the spectrum of frequencies of a signal as it varies with time. When applied to an audio signal, spectrograms are sometimes called sonographs, voiceprints, or voicegrams. When the data is represented in a 3D plot they may be called waterfalls.