Tinyscript tool to bruteforce the password of a PDF

README.md

PDF password bruteforcer

This is a small tool using Tinyscript and pypdf or pikepdf to bruteforce the password of a PDF given an alphabet (defaults to printables) and a length (default is 8).

$ pip install pypdf tinyscript
$ tsm pdf-password-bruteforcer

pdf-password-bruteforcer.py

#!/usr/bin/python3
from tinyscript import *
try:
    import pikepdf
    BACKEND = "pikepdf"
except ImportError:
    import pypdf
    BACKEND = "pypdf"


__author__    = "Alexandre D'Hondt"
__version__   = "1.4"
__copyright__ = ("A. D'Hondt", 2020)
__license__   = "gpl-3.0"
__docformat__ = "md"
__examples__  = ["secret.pdf -p '[a-z0-9]{5}'"]
__doc__       = """
*PDF Password Bruteforcer* allows to execute a bruteforce attack on a given PDF file,
 setting a regular expression pattern for the target password.
"""

BANNER_FONT  = "tombstone"
BANNER_STYLE = {'fgcolor': "lolcat"}


def bruteforce_pdf_password(path, regex):
    if BACKEND == "pypdf":
        with open(path, 'rb') as f:
            reader = pypdf.PdfReader(f)
            for p in ts.bruteforce_re(regex):
                logger.debug(p)
                try:
                    reader.decrypt(p)
                    len(reader.pages)
                    logger.success("FOUND: " + p)
                    return True
                except pypdf.errors.FileNotDecryptedError:
                    pass
                except Exception as e:
                    logger.exception(e)
                    break
    else:
        for p in ts.bruteforce_re(regex):
            logger.debug(p)
            try:
                with pikepdf.open(path, password=p) as f:
                    logger.success("FOUND: " + p)
                    return True
            except pikepdf._qpdf.PasswordError:
                pass
            except Exception as e:
                logger.exception(e)
                break
    return False


if __name__ == '__main__':
    parser.add_argument("file", type=ts.file_exists, help="encrypted PDF file")
    parser.add_argument("-p", "--pattern", default="^[0-9a-zA-Z!-_]{1,8}", help="password pattern")
    initialize(add_time=True, noargs_action="demo", action_at_interrupt="confirm")
    logger.info("Starting PDF password bruteforce...")
    logger.handlers[-1].terminator = ""
    if not bruteforce_pdf_password(args.file, args.pattern):
        logger.failure("Password not found")

test.pdf.gz.b64
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As a warning for other users tinyscript has an incredible number of dependencies so you may want to use a dedicated environment when installing it.

Here's a little dockerfile if anyone wants it. Just need to put the script in the same folder as this Dockerfile

# Build
FROM centos:7.9.2009

# set environment variables
ENV PYTHONDONTWRITEBYTECODE 1
ENV PYTHONUNBUFFERED 1

ENV APP_HOME=/app
WORKDIR $APP_HOME

# install system dependencies
RUN yum update -y && \
    yum install -y gcc python3 python3-pip python3-devel
RUN pip3 install --upgrade pip

# Install reqs and copy over files from context
COPY . $APP_HOME
RUN chmod +x $APP_HOME/*
RUN pip3 install pypdf tinyscript

docker build -t pdftool .
docker run --rm -it pdftool /bin/bash
>> python3 pdf-password-bruteforcer.py <filename>