Razi CTF - Writeup

This blog post contains the writeups for:

 

l Cryptography

n Ladder

 

l Steganography

n Culture

 

l Misc

n Sanity Check

 

 

 

LADDER

The question actually contains the hint for this one.

 

The given string (GN2WUSTOLFYTCWKQLFLG65KBNVDEGMRUMMZTM4LVOFUG2R3LMNWTKTCMGVWVUR3WOM3HONDNMV3UOOKDM4ZWUTDIK5FGOY3EJV4VIMKFJUYVUWLQGJRUGYLCOQ3HG6LVHFXUC3TKJRSW6RDLNFFEWZ2TG4) is a base 32 string which is decoded using cyberchef.

Result: 3ujJnYq1YPYVouAmFC24c36quqhmGkcm5LL5mZGvs6w4mewG9Cg3jLhWJgcdMyT1EM1ZYp2cCabt6syu9oAnjLeoDkiJKgS7

 

Then its decoded using base 58.

B3ubcEe7waVuE55z96FTrO8JvfuevhFXEhXqzkWINOiIaRd4OlGLhL5jgqUXaQRwNC0CXl

 

Then 62.

O0lPbGM2Vz9PJUc7RVNyMFFeWVlDaSFJIzg3Yy1wQDNkWE1JLw

 

Then 64.

;IOlc6W?O%G;ESr0Q^YYCi!I#87c-p@3dXMI/

 

Finally base 85

RaziCTF{w3_G0t_4ll_tHe_Ba$3s}

 

Thus the flag for this challenge is RaziCTF{w3_G0t_4ll_tHe_Ba$3s}

 

 

 

 

CULTURE

The data is encoded in the least significant bits of the image and can be retrieved using zsteg.

 

The flag for this is RaziCTF{i_s33_ur_4_MaN_0f_LSB_aS_W3LL}

 

 

 

 

SANITY CHECK

 

The flag is at the end of the rules page.

 

The flag for this one is RaziCTF{S0_iT_b3G1Ns}