Crack PDF files using a date as the password. This script enumerates dates as well as can read in a list of passwords to try.

pdf_crack.py

#!/usr/bin/env python3
import os
from datetime import datetime
from typing import Optional
import argparse

import pikepdf
from tqdm import tqdm


# Generate a list of passwords of every date in MMddyyyy format
def dates_between_years(start_year: int = 2000, end_year: int = 2020) -> list:
    passwords = [
        str(i).zfill(2) + str(j).zfill(2) + str(k).zfill(4)
        for i in range(1, 13)
        for j in range(1, 32)
        for k in range(start_year, end_year)
    ]
    return passwords


def crack_pdf(
    pdf_file: str, passwords: list, save_unencrypted: bool = False
) -> Optional[str]:
    # Check if pdf_file is a valid file
    if not os.path.isfile(pdf_file):
        print("[-] File does not exist")
        return None

    # Loop through all passwords in the list
    for password in tqdm(passwords, "Decrypting PDF", unit=" passwords"):
        try:
            # Try to open the pdf file with the password
            with pikepdf.open(pdf_file, password=password) as pdf:
                # Password decrypted successfully, break out of the loop
                if save_unencrypted:
                    pdf.save(f"{pdf_file}.decrypted")

                return password
        except pikepdf._qpdf.PasswordError:
            # Password was incorrect, continue to the next password
            continue
        except pikepdf._qpdf.PdfError:
            # File is not a valid pdf file, break out of the loop
            print("[-] File is not a valid pdf file")
            break
    return None


def get_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(
        description="Crack PDF files using a wordlist of dates"
    )
    parser.add_argument(
        "pdf_file",
        type=str,
        help="PDF file to crack",
        metavar="PDF_FILE",
    )
    parser.add_argument(
        "--save",
        action="store_true",
        help="Save decrypted PDF file",
    )
    parser.add_argument(
        "--wordlist",
        type=str,
        help="Wordlist of dates to crack",
        metavar="WORDLIST",
    )
    parser.add_argument(
        "--start-year",
        type=int,
        help="Start year of dates to crack",
        metavar="START_YEAR",
    )
    parser.add_argument(
        "--end-year",
        type=int,
        help="End year of dates to crack",
        metavar="END_YEAR",
        default=datetime.now().year,
    )
    return parser.parse_args()


def main():
    args = get_args()

    passwords = []
    if args.wordlist:
        passwords = [line.strip() for line in open(args.wordlist)]
    if args.start_year:
        passwords.extend(dates_between_years(args.start_year, args.end_year))

    correct_password = crack_pdf(args.pdf_file, passwords)
    if correct_password:
        print("[+] Password found:", correct_password)
    else:
        print("[-] Password not found")


if __name__ == "__main__":
    main()

PDF_Crack_README.md

PDF Crack

Table of Contents

• About
• Getting Started
• Usage

About

This project is a simple PDF cracker. It is written in Python and uses the pikepdf library.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Prerequisites

What things you need to install the software and how to install them.

pip3 install -r requirements.txt

Usage

$ python3 pdf_crack.py -h
usage: pdf_crack.py [-h] [--save] [--wordlist WORDLIST]
                    [--start-year START_YEAR] [--end-year END_YEAR]
                    PDF_FILE

Crack PDF files using a wordlist of dates

positional arguments:
  PDF_FILE              PDF file to crack

optional arguments:
  -h, --help            show this help message and exit
  --save                Save decrypted PDF file
  --wordlist WORDLIST   Wordlist of dates to crack
  --start-year START_YEAR
                        Start year of dates to crack
  --end-year END_YEAR   End year of dates to crack

requirements.txt

pikepdf
tqdm