51–60 of 283 posts
Why don't we just stop allowing users to choose their passwords?
The main reason is that, if IT chooses the user passwords, then the users simply forget the password. Thus, the system for resetting a lost password becomes part of the default login process. In which case, you might as well having a password in the first place.
So the system could basically fall back to being OTP?
Here's another problem that isn't discussed very much: error messaging and failure modes. I use a command line tool to generate passwords, and I use a password database to store them. It has happened to me before that the maximum password length is something disconcertingly small, like 20 characters. I would copy and paste my password, submit, and then failed to be able to login. Why? Because my password in the "crea…
I read a recent anecdote bout a similar issue. The person had their long password silently truncated to 21 chars on the reset page and 20 chars on the login page. That sounds like a super fun thing to track down as an end user.
This means you can successfully set your password to something you can never enter!
It has been raised in their forum but the discussion there is drowned out by people missing the point entirely. https://community.giffgaff.com/t5/Help-Support/Password-Limi...
I agree with almost everything but the he loses me towards the end: > I had a bit of a sad when I realized that we were perfectly fine with users selecting a 10 character password that was literally "aaaaaaaaaa". In my opinion, the simplest way to do this is to ensure that there are at least (x) unique characters out of (y) total characters. Isn't that exactly what you're complaining about with your arbitrary passwor…
I'm surprised that this article didn't mention the most important point about password rules: They force you to come up with a new password that you probably haven't used before and so you will probably forget it. There are websites that I don't use often where I literally have to reset the password (and go through all the i-forgot-my-password steps) every time I want to log in because they forced me to come up with…
Indeed and then one's email potentially becomes the weakest link in one's password security.
Here's another problem that isn't discussed very much: error messaging and failure modes. I use a command line tool to generate passwords, and I use a password database to store them. It has happened to me before that the maximum password length is something disconcertingly small, like 20 characters. I would copy and paste my password, submit, and then failed to be able to login. Why? Because my password in the "crea…
> Why? Because my password in the "create" page was silently truncated on the front end, but the same truncation does not occur in all places, so I would type a longer password on the login page then what was registered in the system and it would fail. Here's an even worse one than truncating the end of long passwords: truncating internal whitespace The change/reset password dialog for Apple ID does this. If your pas…
No, but the time spent computing the hash does change and you open yourself to denial of service attacks. Just pick a max password length of like 200, or whatever your hashing algorithm mandates (55 for bcrypt).
Earlier quoted context omitted.
> Why? Because my password in the "create" page was silently truncated on the front end, but the same truncation does not occur in all places, so I would type a longer password on the login page then what was registered in the system and it would fail. Here's an even worse one than truncating the end of long passwords: truncating internal whitespace The change/reset password dialog for Apple ID does this. If your pas…
> Also you can work around that by hashing the entire uses password (with say SHA-512) prior to inputting into bcrypt. I wonder why people are so eager to combine different hash algorithms, especially a strong with a weaker one. If this is isn't a well-established anti-pattern, it should become one.[1] Why? Because in some sense it combines the weaknesses of both algorithms. Assume your password hash is: h(p) = bcryp…
What I'd consider a much worse issue is considering the following to be the same by silently truncating things:
- some really long password ... that ends with foo
- some really long password ... that ends with bar
- some really long password ... that ends with baz
The only acceptable alternatives when using something like bcrypt are:
- Restrict user passwords to 72 bytes (not chars!)
- Hash with something like SHA-512 prior to passing them to bcrypt.
I agree with almost everything but the he loses me towards the end: > I had a bit of a sad when I realized that we were perfectly fine with users selecting a 10 character password that was literally "aaaaaaaaaa". In my opinion, the simplest way to do this is to ensure that there are at least (x) unique characters out of (y) total characters. Isn't that exactly what you're complaining about with your arbitrary passwor…
It's not an illusion, 1q2w3e4r5t is indeed better than aaaaaaaaa, even if it's just the numbers interleaved with qwerty (and probably easy to brute force generate up to it).
>if I use "aaaaaaaaa" as a password on a website I know full well what I'm doing. So why even bother?
Because not everyone who uses "aaaaaaaaa" (or "1q2w3e4r5t" for that matter) knows "full well" that it's insecure?
I'm surprised that this article didn't mention the most important point about password rules: They force you to come up with a new password that you probably haven't used before and so you will probably forget it. There are websites that I don't use often where I literally have to reset the password (and go through all the i-forgot-my-password steps) every time I want to log in because they forced me to come up with…
Earlier quoted context omitted.
> if I use "aaaaaaaaa" as a password on a website I know full well what I'm doing You do. A lot of users don't consider automation when it comes to people hacking their account. I've heard "Nobody will ever guess it though" a few times during my career.
I am being serious when I ask this question: does anybody brute force passwords? I posit that using a unique password for every single website is sufficient, because no one brute forces passwords. What attack vector is a password with high entropy protecting against? The only one I can think of is an unreported database leak. The attacker may be able to more easily reverse the password hash and use your account on th…
I'm no security expert, but I start to wonder if the "practical" entropy of a given password is actually much higher than the theoretical entropy numbers people derive.
Serious question: when is the last time anyone has had an account compromised because of a weak password?
Earlier quoted context omitted.
> if I use "aaaaaaaaa" as a password on a website I know full well what I'm doing You do. A lot of users don't consider automation when it comes to people hacking their account. I've heard "Nobody will ever guess it though" a few times during my career.
I am being serious when I ask this question: does anybody brute force passwords? I posit that using a unique password for every single website is sufficient, because no one brute forces passwords. What attack vector is a password with high entropy protecting against? The only one I can think of is an unreported database leak. The attacker may be able to more easily reverse the password hash and use your account on th…
Very many people. And not all systems stop them from doing so.
And database leaks happen all the time too...