Encrypted Files

Encrypted zip files may appear as regular zip files and when unzipped without a password the files will simply unzip without any errors. The files will turn out to be empty and a user may easily miss reading sensitive information from the files.

An encrypted zip file can be cracked by first extracting the hash using John and then cracking the password using John again.

The hash can be extracted using,

zip2john <encrypted file> > filename.hash

Then the hash can simply be cracked using hash with an appropriate wordlist,

john filename.hash

The encrypted file can be unziped using 7zip,

7z x <encrypted file>