Zxcvbn: realistic password strength estimation • Hacker News Board

Re: Zxcvbn: realistic password strength estimation

#111

Post by richardw » Wed, Apr 11, 2012, 6:31 AM UTC

RandallBrown wrote: post #10

I hate when they won't let me use a password that's not "strong" enough. I picked my password, let me use it. I know the consequences of using an easy password.

Having stronger passwords reduces the risks to them as well. Support costs when your account is hacked, news flow when accounts are broken into (which often don't discriminate between the app's fault and the user's). If all passwords are strong, a password dump has reduced risk.

After having two of my passwords leaked via app breakins, I now use a password manager and make sure even the most arb of sites share nothing, each password is strong, and my master password is first class. Sure there's still a risk. Much lower than before.

Re: Zxcvbn: realistic password strength estimation

#112

Post by ch0wn » Wed, Apr 11, 2012, 6:55 AM UTC

chimeracoder wrote: post #89

ch0wn wrote: post #53

Earlier quoted context omitted.

Whenever I come across a site that refuses to let me sign up with a secure password, I either leave right away or send them a short mail first. There were times where I had to rely on password managers too, though. Banking sites are one common place ...

>Banking sites are one common place ... I can't tell you the number of times I've tried to explain to banks that 'security questions' are absolutely worthless, and that their 'secure password' policy is actually worse than no policy at all. One bank actually requires passwords to be between 6 and 8 characters in length, with at least one letter and one number and no special characters .

This is exactly what my bank requires. Worst part after I told them that this is irresponsible: A few years ago they only allowed a 5-digit PIN for their web login.

Re: Zxcvbn: realistic password strength estimation

#113

Post by lloeki » Wed, Apr 11, 2012, 7:17 AM UTC

ch0wn wrote: post #112

chimeracoder wrote: post #89

Earlier quoted context omitted.

>Banking sites are one common place ... I can't tell you the number of times I've tried to explain to banks that 'security questions' are absolutely worthless, and that their 'secure password' policy is actually worse than no policy at all. One bank actually requires passwords to be between 6 and 8 characters in length, with at least one letter and one number and no special characters .

This is exactly what my bank requires. Worst part after I told them that this is irresponsible: A few years ago they only allowed a 5-digit PIN for their web login .

Mine used to beat yours by one, as the code was by default the actual PIN of my credit card, while the username itself was 6 digits. It's so... vile I can't even begin to describe it.

Re: Zxcvbn: realistic password strength estimation

#114

Post by rplnt » Wed, Apr 11, 2012, 9:18 AM UTC

tomp wrote: post #71

Lagged2Death wrote: post #28

I'm surprised to see that "correct horse battery staple" type pass-phrases really have to be quite long to score well, but that even comically short email addresses ("dlk3@mit.edu") score very highly. In fact, it looks like my ever-so-clever words-and-numbers web passwords ("Happy314Day") are all terrible, but all my email addresses all make maximum strength 4-point passwords. I wonder if that's because email address…

In general, email addresses should make quite good passwords (two.words@domain.tld). However, limiting yourself to yourname.yoursurname@yahoo/google.com reduces the entropy a lot. Also, the idea of passwords are easy-to-remember&hard-to-guess. The only emails easy to remember are the one's you're using currently, which shouldn't be to hard for an attacker to figure out (in general).

What about:

simplepassword@domainimregistering.on

Easy to remember yet hard to guess. (Unless you read this comment)

Re: Zxcvbn: realistic password strength estimation

#115

Post by rplnt » Wed, Apr 11, 2012, 9:21 AM UTC

sjwright wrote: post #100

$^$^$^_ = crack time 26 days $^$^$^i = crack time 3 months $^$^$^z = crack time 5 years Should the result vary so widely given the arguably minor variation?

One of the cases I tried was:

notaword12 - 17 hours

notawrod123 - 22 minutes

With almost any not-word, really. The extra 12 is better than 123 somehow.

Re: Zxcvbn: realistic password strength estimation

#116

Post by shawabawa » Wed, Apr 11, 2012, 9:32 AM UTC

Game_Ender wrote: post #79

jstalin wrote: post #78

Earlier quoted context omitted.

10-character apha-numeric password is crackable in a matter of days: http://whitepixel.zorinaq.com/

Does that break more then md5? I thought it was well known that md5 was a bad password hash algorithm.

MD5 is bad because it suffers from collision attacks, however it doesn't suffer from preimage attacks, so it's actually fairly secure for passwords (although I still wouldn't use it over any modern algorithm).

Basically, you can make 2 arbitrary pieces of data have the same hash, but you can't create a piece of data matching a known hash.

Re: Zxcvbn: realistic password strength estimation

#117

Post by shawabawa » Wed, Apr 11, 2012, 9:35 AM UTC

idupree wrote: post #107

elithrar wrote: post #87

Earlier quoted context omitted.

> It always bothers me a bit when I see analysis of password strength for compromised sites without any mention of the possibility that the account might just not be important to users. I actually use that as a factor when considering a password. If I think the site isn't going to be the most secure (a phpBB forum, or hand-rolled web-app), then I'm more likely to use a simple (but still relatively decent) password.

Recently I made a new password for some random site (and keep an encrypted record of it). Then I was relieved I did, because the site turned around and emailed the password right back to me. Unencrypted. In plaintext. Hmm, that is wrong enough that I'll call them out by name... https://www.nbotickets.com/ (Is it polite and useful to email them how I feel about that? I feel like I'd just be "someone-is-wrong-on-the-in…

If anything it would irresponsible not to tell them.

Re: Zxcvbn: realistic password strength estimation

#118

Post by midnight_city » Wed, Apr 11, 2012, 9:40 AM UTC

16s wrote: post #37

Many sites won't accept my passwords (SHA1_Pass). They say that they are too long or have inappropriate chars or that they are not complex enough. Here's an example of inappropriate chars: UTP+NnhabgHKx6 So I make a different password and the sites say it is too weak as it has no special chars or uppercase chars: 5133fe36785a6e01cac7a68c9c111afff5bb4821 So I give up and type Password1 which is normally accepted.

I recommend PwdHash [https://www.pwdhash.com/]. It has extensions for Chrome, Firefox, and Opera, and I have not yet had a site complain about its generated passwords.

zxcvbn assigned my generated password for their site a crack time of ~21 million years.

Re: Zxcvbn: realistic password strength estimation

#119

Post by vog » Wed, Apr 11, 2012, 10:01 AM UTC

eblume wrote: post #61

wh-uws wrote: post #39

I have waited for this for so long. I'm glad someone finally took it up and and more importantly that its on a site as popular as dropbox. (this way hopefully the thinking will gain some traction) Every time I'm forced to have a password with 3 or 4 character classes I sigh and think of that xkcd comic Edit: also try typing the password from the xkcd comic here https://www.dropbox.com/register nice touch

For the lazy, if you enter "correcthorsebatterystaple" the password strength gets set to "lol" with an info-box that reads something along the lines of "Don't take the webcomic too seriously. :)"

I find that message misleading. The xkcd comic does have a point, and thus should be taken seriously. (Despite the obvious downside that those passwords take longer to type, which is why I still prefer short, cryptic passwords.)

So a better message might be:

"Don't follow the webcomic too closely. :)"

Re: Zxcvbn: realistic password strength estimation

#120

Post by bad_user » Wed, Apr 11, 2012, 10:02 AM UTC

Shank wrote: post #84

The real problem with humans is that passwords are still hard to remember for multiple services. Doesn't matter if you have a secure password and it's used everywhere. Likewise, if it's used with LastPass or 1Password style services, you face the problem of dealing with entering it. Though a desktop PC is fine for this, the best counter-examples are mobile devices. LastPass on mobile: 1. Use app that needs a password…

The rule of thumb I'm using for password management ... if losing everything means you'll lose your passwords, then that's not good password management. But you also need unique passwords for each service.

My passwords are generated using HMAC_SHA256( global password, domain_name, salt ). My global passwords is a 7 words phrase, contains capitalization and 2 words that are not in the dictionary. Each password generated is unique for each website and reasonably long (settled on 32 chars).

This is not perfect but works well.

Related to your problem of usability ... I use Firefox on my mobile and through Firefox Sync I get all cookies synchronized from my laptop. Meaning that I am rarely required to enter passwords on my mobile.