How to find a password for a password-protected ZIP? Exploring Brute-forcing Tools & 7-Zip, by Dr Josh Stroschein - The Cyber Yeti on YouTube. 9 min 9 s.
- Video length
- 9 min 9 s
- Time to do it
- 20 minutes
- Difficulty
- Medium
- Steps
- 8
What you need
Steps
Confirm the archive is yours or that you have permission to open it. Install 7-Zip, right-click the ZIP and choose Open archive to see the file list before you try any password.
Check the Method column in 7-Zip. Entries marked with encryption need a password, but any plain entry can be selected and pulled out with the Extract button right away.
Extract and read every unencrypted file you can, such as readme, notes or info files. Passwords are often written inside the archive, and the filenames themselves can hint at one.
Install Python 3 and download zipdump.py from Didier Stevens. Run python zipdump.py yourfile.zip to list the archive contents and confirm how the data is encrypted.
Test a single guess by passing the password option, for example python zipdump.py -p guess yourfile.zip. It tells you whether that password decrypts the data.
For a real search, turn the archive into a hash. Run zip2john yourfile.zip > hash.txt, which ships with John the Ripper, to write a crackable hash file.
Run john --wordlist=rockyou.txt hash.txt. John works through the wordlist in order and stops when it finds the password that opens the archive.
Type john --show hash.txt to print the recovered password. Open the ZIP in 7-Zip again, choose Extract To, and enter the password to unpack everything.
Tips and common mistakes
Only run these tools on archives you own or have written permission to access, since cracking someone else's file is usually illegal.
Try the archive name, the site name and simple variations by hand first, because many ZIPs use a short or obvious password.
ZipCrypto archives crack far faster than AES-256 ones, so check the encryption method before assuming a search will be quick.
Unencrypted files inside the archive are the most common way a password leaks, so always look there before brute-forcing.
Questions
Can I open the ZIP without the password at all?
Only partly. 7-Zip can list every file and extract the ones that were never encrypted, but encrypted entries stay locked until you supply the password.
How long does the password search take?
It depends on password length, the wordlist and the encryption type. A short password in a ZipCrypto archive can fall in seconds, while long AES passwords may never be found by brute force.
Is it legal to recover a ZIP password?
It is fine on archives you created or have permission to access, such as files from your own backup. Doing it on someone else's file without consent can break the law.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
