Slashdot Mirror


An Algorithm For Better Password Checking (technologyreview.com)

New submitter della writes: Password checkers — those things that tell you whether your password is strong or not — are good: various studies have found that they make users choose better passwords. Unfortunately, nowadays attackers use probabilistic strategies based on natural language processing to guess passwords earlier, and most checkers consist of heuristic rules that don't reflect well probabilistic attacks. To do better you could in theory simulate the attack, but if your password is not that bad, that would be very expensive or just unfeasible.

In a paper I wrote with Maurizio Filippone and presented at ACM's CCS conference, we show how you can take an attack model and a password, and through a simple formula come up quickly with a reliable estimation of how many guesses that attack would need to guess the password. You can use this to roll a better password checker, or — as we've also done in the paper — to compare different attacks.

2 of 103 comments (clear)

  1. STOP IT! by Anonymous Coward · · Score: 2, Insightful

    Stop saying my password is bad. If I make it more complicated, I won't remember it. So it would be even worse.
    And making me change it every now and then is even more stupid.

  2. Here's an idea by Nidi62 · · Score: 3, Insightful

    Stop making us change them every 3 months and we could come up with stronger passwords.

    --
    The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil