Waraxe Forums

Munchieman · Beginner

Hello,
I haven't seen much here about zip files, so I may be barking up the wrong tree. I am attempting to crack a zip file I created a long time ago. It is a zip file that is about 850K named temppix.zip. It contains 1 file called other pix. The file is encrypted too. I tried using the Passware software for a few days, but I'm past all of the normal short cuts, and using simple brute force. I don't ever remember using a password that is less that 10 characters, and I don't have the months it will take to brute force the file.
After the various attacks, it comes up with some text that seems to include an MD5, but the online MD5 engines say that it isn't.

Protection: Zip 2.0 - Extraction Password, Default encryption
Complexity: Brute-force - Fast
MD5: 079D883C35C1B556BEBA786C65CD177D

Any suggestions on how I can open this file? Or, even get a list of the files that are within the otherpix.zip file?
Thanks for the help!
Munchieman

waraxe · Site admin

Zip 2.0 encryption scheme is cryptographically weak and this is know allready long time, for example:

http://archive.cert.uni-stuttgart.de/vuln-dev/2003/02/msg00019.html

There are password crackers, which can decrypt ZIP archive contents within reasonable timeframe:

http://www.elcomsoft.com/archpr.html

Munchieman · Beginner

Hey Waraxe,
Thanks for the reply. The weakness seems to be available when the file contains more than 3 to 5 files. I don't remember why, but I wanted to protect the file names, so I ziped the files into an encrypted archive that hides the filenames, and then zipped that archive into another encrypted archive.
The software you suggested has been tried, and says that it can't do the guaranteed zip crack because of there only being 1 file in the archive.
Any idea what kind of MD5 hash the Passware software showed?
MD5: 079D883C35C1B556BEBA786C65CD177D
Thanks again!
Munchieman