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Security Businesses Google The Internet

Using Google To Crack MD5 Passwords 232

stern writes "A security researcher at Cambridge was trying to figure out the password used by somebody who had hacked his Web site. He tried running a dictionary through the encryption hash function; no dice. Then he pasted the hacker's encrypted password into Google, and voila — there was his answer. Conclusion? Use no password that any other human being has ever used, or is ever likely to use, for any purpose. I think."
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Using Google To Crack MD5 Passwords

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  • by owlstead ( 636356 ) on Tuesday November 20, 2007 @05:40PM (#21427063)
    But if I ever need to run a hash against a password database, I'll remember this lesson and first perform a Google search. Saves a lot of time and CPU cycles.

    I am already doing this for telephone calls I cannot place. If it's an institution or a person that is calling because of profession, the chances that the telephone is listed somewhere on a (search engine) accessible web page is *very* large.
  • Re:Salt (Score:3, Insightful)

    by Anonymous brave dude ( 950545 ) <gavinwahl@gmail.com> on Tuesday November 20, 2007 @05:51PM (#21427253)
    Use a crazy fucking password, but you don't have to remember all of it.
  • by CastrTroy ( 595695 ) on Tuesday November 20, 2007 @05:51PM (#21427257)
    I've also started doing this for telephone numbers. Any number I don't recognize, I let the answering machine deal with it. If they don't leave a message, their call isn't important. Also, if you look up the number, just to make sure you didn't miss anything, then you can often find complaint sites when the number belongs to a telemarketer. I think just about every number I've ever looked up that didn't leave a message was a telemarketer.
  • Re:Salt (Score:5, Insightful)

    by Em Adespoton ( 792954 ) <slashdotonly.1.adespoton@spamgourmet.com> on Tuesday November 20, 2007 @05:55PM (#21427323) Homepage Journal

    agree, but this isn't something the user can do. I can't register for a site and say, "I need to remember to use salt!" The site has to implement it and implement it correctly.

    The guy posting was posting from the perspective of the user, not the author of the system. The conclusion from the summary is still accurate since you can't make the assumption that salt is always used. The next best defense is a crazy fucking password.


    This is why my passwords are themselves salted hashes. The likelihood of someone else using my passwords is the same as a regular hash collision, I get to use a separate password for each place one is required, and the hashing mechanism and salt are simple enough for me to keep in my head. End result: infinite number of easily generatable and retrievable passwords that look just like a hashed password when decoded.
  • Re:Salt (Score:5, Insightful)

    by Sangui5 ( 12317 ) on Tuesday November 20, 2007 @05:58PM (#21427367)
    Rainbow tables? Salting breaks it.
    Precomupted dictionaries? Salting breaks it.
    Brute force and compare against the whole pw list? Salting breaks it.

    Salting is your friend. Long salts don't cost much, but make many attacks completely infeasible. Unix has been using salted passwords since forever. Yet nthash *still* doesn't include a salt.
  • Re:Salt (Score:3, Insightful)

    by repvik ( 96666 ) on Tuesday November 20, 2007 @06:15PM (#21427577)
    If you don't have to remember part of it, why not make the whole password fucking crazy? Since you already have to cut'n'paste, why have a part of the password be easier than another?
  • by LWATCDR ( 28044 ) on Tuesday November 20, 2007 @06:37PM (#21427869) Homepage Journal
    I used to store user passwords in plain text on my website. Before anyone gets all bent. I assigned passwords to the users and didn't let them change them. They where AOL style passwords things like blue#guppy. Also there wasn't any personal info that mattered tied to the password. It was a small site and worked well. They couldn't use one password for this simple message base and there bank account, they couldn't use stupid passwords like their first name, and I could look them up if they forget or for testing.
    When I moved to a CMS we went to hashed passwords.
    Boy is it a pain. Nobody understands that even I can not look at their passwords. Yes a salted hash is the correct and secure way to do things... But it can be a pain in the rear.
  • by nobodyman ( 90587 ) on Tuesday November 20, 2007 @06:50PM (#21428035) Homepage

    No, the conclusion is you should always use salted hashes.
    That's good advice for application developers, but the original post was offering advice to users. Still, even that is a bit of an overreaction. From TFA:

    And indeed, the MD5 hash of "Anthony" was the database entry for the attacker. I had discovered his password.
    Not to diminish this admin's accomplishment (it sounds like he's quite clever), but doesn't this boil down to "don't use your name as your password"? Or better yet, "don't use any proper name as a password".

    Keep in mind that this was a hash of a userid (not a password) that was captured in a google index, and it's highly unlikely that someone will choose a userid on a google-indexed site that just-so-happens to be your 10+ character password that has mixed-case and special characters. I think the same "good password advice" still applies, even in a google-world.
  • by Cairnarvon ( 901868 ) on Tuesday November 20, 2007 @07:03PM (#21428241) Homepage
    He didn't write the WordPress software, and presumably doesn't have the time to audit every bit of code it uses.
    I doubt Bruce Schneier himself audited the entire Movable Type codebase, which he uses for his blog. Does that make Schneier "not much of a security researcher"?
  • Re:french bitch (Score:4, Insightful)

    by maxwell demon ( 590494 ) on Tuesday November 20, 2007 @07:16PM (#21428379) Journal

    I just hate douche bags who can't spell.
    Spelling errors can make your password more secure!
  • by Antique Geekmeister ( 740220 ) on Tuesday November 20, 2007 @07:29PM (#21428537)
    It's no worse than Subversion's insistence on storing user passwords for any protocol but SSH public keys in a local plaintext file.

    Do not *EVER* allow a Subversion system to use the same passwords as the user system, and if you have access to the user's accounts, run a check of their stored Subversion passwords to make sure they didn't use their same password somewhere else as for their local user account.
  • Re:Salt (Score:3, Insightful)

    by Stewie241 ( 1035724 ) on Tuesday November 20, 2007 @07:46PM (#21428771)
    There are programs such as MyPasswordSafe, that allow you to store your passwords in an encrypted form. I have one crazy password that protects all the other passwords. I haven't checked the encryption on it, but I know I need the password (which is stored only in my head), to unlock the other passwords.
  • Re:Salt (Score:2, Insightful)

    by CarAnalogy ( 1191053 ) on Tuesday November 20, 2007 @07:52PM (#21428835)
    This is slashdot, we need a bad car analogy too. :P
  • by Anonymous Coward on Wednesday November 21, 2007 @12:07PM (#21435865)
    You don't realize how many developers have no clue what a salted hash is and how it works. I've had discussion with developers who weren't complete morons when it comes to programming that had no fscking idea what I was talking about. They fully knew what a hash was, but it was unconceivable that you could store a salt value next to a hash. They were massively deniyng that it could work, trying to make fun of me "it's impossible, that's not how cryptographic hashes work" etc.

    On a related side not you'd be amazed at the number of developer that have no fscking clue about how public key cryptosystems works.

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