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Bandit Level 11 → 12

Shubham
Shubham
Cybersecurity Enthusiast

Login: ssh bandit11@bandit.labs.overthewire.org -p 2220
Password: dtR173fZKb0RRsDFSGsg2RWnpNVj3qRr

task​

The password for the next level is stored in the file data.txt, where all lowercase (a-z) and uppercase (A-Z) letters have been rotated by 13 positions.

theory lil bit​

  1. ROT13: This is a simple substitution cipher that replaces a letter with the 13th letter after it in the alphabet. Since there are 26 letters in the English alphabet, applying ROT13 twice restores the original text.
  2. tr (translate): This command is used for translating or deleting characters.
    • The syntax tr 'A-Za-z' 'N-ZA-Mn-za-m' maps the first half of the alphabet to the second half and vice versa.
    • Specifically, it maps A to N, B to O, and so on, effectively shifting everything by 13 places.
  3. Symmetry: ROT13 is its own inverse; you use the exact same command to both encrypt and decrypt the message.

solution​

bandit11@bandit:~$ ls
data.txt
bandit11@bandit:~$ cat data.txt
Gur cnffjbeq vf 7k16JArUVv5LxIuJfsSVdbbtahGlw9D4
bandit11@bandit:~$ cat data.txt | tr 'A-Za-z' 'N-ZA-Mn-za-m'
The password is 7x16WNeHIi5YkIhWsfFIqoognUTyj9Q4

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