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I created a zip file with Gnome Archive Manager (Ubuntu OS). I created the zip file with a password and I am trying to unzip it using the zipfile Python library:

import zipfile file_name = '/home/mahmoud/Desktop/tester.zip' pswd = 'pass' with zipfile.ZipFile(file_name, 'r') as zf: zf.printdir() zf.extractall(path='/home/mahmoud/Desktop/testfolder', pwd = bytes(pswd, 'utf-8'))

When I run this code I get the following error and I am pretty sure that the password is correct. The error is:

File "/home/mahmoud/anaconda3/lib/python3.7/zipfile.py", line 1538, in open raise RuntimeError("Bad password for file %r" % name) RuntimeError: Bad password for file <ZipInfo filename='NegSkew.pdf' compress_type=99 filemode='-rw-rw-r--' external_attr=0x8020 file_size=233252 compress_size=199427>

How can I unzip the file?

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  • I tried your code and it worked for me, can you unzip it with another program with the same password? Commented May 30, 2020 at 18:51
  • Why is the filename in the exception 'NegSkew.pdf'? Commented May 30, 2020 at 18:55
  • I tried unzipping the file with winrar and 7z and both worked fine and the password is correct all of that is done on a windows machine @NicoMüller Commented May 30, 2020 at 18:57
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    Hmm. This is an interesting question, and I am able to reproduce your observations. I am running on Ubuntu 18.04.4 LTS, with Python 3.7.5. I made a simple text file, zipped & encrypted it in the Gnome Archive Manager. Like yourself, when I try to perform extractall, I am seeing Bad password for file <ZipInfo filename='sample.txt' ...>. This is definitely getting an up-vote from me, and I am going to poke at it a bit. I am inclined to think that Python's builtin ZIP library may not support the encryption algo used by Gnome's Archive Manager, but I don't have any thing to back that up yet. Commented May 30, 2020 at 19:16
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    @liorr The exception shows the name of the file that was to be extracted from the zip Commented May 30, 2020 at 19:42

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zipfile library doesn't support AES encryption (compress_type=99) and only supports CRC-32 as mentioned in the _ZipDecrypter code (https://hg.python.org/cpython/file/a80c14ace927/Lib/zipfile.py#l508). _ZipDecrypter is called and used right before that particular RuntimeError is raised in ZipFile.open which can be traced from extractall.

You can use pyzipper library (https://github.com/danifus/pyzipper) instead of zipfile to unzip the file:

import pyzipper file_name = '/home/mahmoud/Desktop/tester.zip' pswd = 'pass' with pyzipper.AESZipFile(file_name) as zf: zf.extractall(path='/home/mahmoud/Desktop/testfolder', pwd = bytes(pswd, 'utf-8'))
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