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pico CTF Web Cryptography

 November 30, 2021    CTF

Mod 26

The flag picoCTF{next_time_I'll_try_2_rounds_of_rot13_wqWOSBKW} was ROT 13 encoded, it can be solved with CyberChef.


13

The flag picoCTF{not_too_bad_of_a_problem} was ROT 13 encoded, it can be solved with CyberChef.


The Numbers

We get the flag picoCTF{thenumbersmason} by writing down the letters corresponding to the nth place in the alphabet.

corresp = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
cipher =['1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23', '24', '25', '26']
enflag = '16 9 3 15 3 20 6 { 20 8 5 14 21 13 2 5 18 19 13 1 19 15 14 }'
deflag = ''

for i in range(len(enflag)):
    if enflag[i] == '{':
            deflag += '{'
            continue
    elif enflag[i] == '}':
            deflag += '}'
            continue
    elif enflag[i] == ' ':
            deflag += ' '
            continue
    for j in range(len(cipher)):
        if enflag[i] == cipher[j]:
            deflag += corresp[j]

print(deflag)