9 votes

Topic deleted by author

6 comments

  1. [5]
    Crestwave
    Link
    You'd probably have to brute force it. Do you know around how long your password was?

    You'd probably have to brute force it. Do you know around how long your password was?

    5 votes
    1. [4]
      pseudolobster
      Link Parent
      And also are your passwords typically based on words that are in the dictionary?

      And also are your passwords typically based on words that are in the dictionary?

      3 votes
      1. [4]
        Comment deleted by author
        Link Parent
        1. [2]
          Crestwave
          (edited )
          Link Parent
          That would probably take a while to crack, but is probably feasible depending on your hardware, if it's on the low end of characters and you're not in a hurry. I'm not an expert in this, but it...

          That would probably take a while to crack, but is probably feasible depending on your hardware, if it's on the low end of characters and you're not in a hurry. I'm not an expert in this, but it seems that John the Ripper has a zip2john program to extract the hash of a zip file, then you could brute force it normally; HashCat would probably be the best since it's the fastest, I think

          EDIT: Note that by the "low end of characters" I meant if it's 8 rather than 12 in the range you specified below. As @pseudolobster said, if it's as complicated as that example, it would be unfeasable to crack unless perhaps you rent a cluster, which would be expensive. I recommended HashCat over JTR as IIRC HashCat can use both the CPU and GPU while JTR can only use the CPU, so it's faster.

          7 votes
          1. whisper
            Link Parent
            Hashcat is likely the best option, once you have the hash. The newest version of Hashcat has support for PKZIP Hashes, which allows very quick recovery of passwords from .zip archives that use the...
            • Exemplary

            Hashcat is likely the best option, once you have the hash. The newest version of Hashcat has support for PKZIP Hashes, which allows very quick recovery of passwords from .zip archives that use the pkzip encryption. They actually used this to guess all passwords up to 15 characters in under 15 hours.

            If @suspended encrypted this file with a tool that uses PKZIP, then they might be in luck.

            10 votes
        2. pseudolobster
          Link Parent
          If your password is as complex as that example, you're pretty much screwed. I checked a password strength calculator and it says it would take 204 million years to crack that. If it's a dictionary...

          If your password is as complex as that example, you're pretty much screwed. I checked a password strength calculator and it says it would take 204 million years to crack that. If it's a dictionary word with numbers at the end it's trivial and could take mere seconds.

          The most commonly used tool used to brute-force passwords is john the ripper. It's a bit complicated to use, but very powerful. You can feed it a dictionary or just tell it to start at "a" and cycle through every possible combination of letters. You can give it rules in the form of regular expressions to try different permutations of your dictionary words, say, swap zeroes for O's etc. There's a number of tutorials online, and I was able to find a bunch in a quick google / ddg search just by looking up "john zip"

          4 votes
  2. gpl
    Link
    This is a low tech solution, but if you reuse passwords check and see what passwords you used for accounts created near that time. This has helped me more than once.

    This is a low tech solution, but if you reuse passwords check and see what passwords you used for accounts created near that time. This has helped me more than once.

    3 votes