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Bitwarden design flaw: Server side iterations

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21–30 of 264 posts

Re: Bitwarden design flaw: Server side iterations

#21
post #14

I still haven't seen a clear explanation of how the # of iterations scales in relation to password length. If it is true a few extra characters is as good as having sky-high iterations, the guidance should be on 'forcing' users choose long-enough passwords, not in this nitpicking over the 'right' # of iterations.

Number of iterations being discussed is how many times the password is hashed. It is a setting the system chooses and is independent of the password length the user chooses. If you are asking if the length of the password by itself be sufficient to create a secure password, then the answer is mostly no. You need many iterations of the hashing process otherwise brute force attacks become trivial given today's hardware…

Unless you have a high-entropy long password. 10 Diceware words (words chosen uniformly at random from a list of 7776 words) is over 128 bits of entropy, even a very fast hash would be enough for such a passphrase. Of course at that point you've essentially memorized a cryptographic key, not a traditional low-security password. Good for the master password of a password database, not so usable anywhere else.

Re: Bitwarden design flaw: Server side iterations

#22
post #15

I still haven't seen a clear explanation of how the # of iterations scales in relation to password length. If it is true a few extra characters is as good as having sky-high iterations, the guidance should be on 'forcing' users choose long-enough passwords, not in this nitpicking over the 'right' # of iterations.

The number of iterations scales linearly with the cost of brute-forcing. The cost scales exponentially with the length of the password, assuming a random password (stops scaling when you reach the hash size I think). Both are important because you can't freely increase the password length, they become more annoying to enter and remember.

If your first two statements are correct I can't see how the third can't be.

If we choose our password from only ~24 chars then you can get the same effect of 100K iterations form just 4 more characters, or ~1 more dictionary word.

That doesn't seem excessive

Re: Bitwarden design flaw: Server side iterations

#23
post #20
post #16

Earlier quoted context omitted.

Even a fairly middling password manager implementation is better than just about any other strategy that anyone is likely to use. Especially because for the vast majority, the other strategy is going to be reusing the same password ~everywhere and if you're lucky the might use a special password for their bank or something.

I guess for most people online, writing all their passwords down in a notebook is more secure than using a password manager. It’s just less convenient.

The notebook is still less secure because of phishing

Re: Bitwarden design flaw: Server side iterations

#24
post #11

Oof, my Bitwarden account was created a while ago and was set to only 5,000 iterations. You can see and change the number of iterations here: https://vault.bitwarden.com/#/settings/security/security-key... (or if you don't trust links for something like your password manager: log into your web vault, click on the top-right dropdown menu, then Account settings > Security > Keys). I've updated it to 600,000 iterations…

Thank you! Mine was also set to 5000, updated to 600k.

Re: Bitwarden design flaw: Server side iterations

#25
post #15

I still haven't seen a clear explanation of how the # of iterations scales in relation to password length. If it is true a few extra characters is as good as having sky-high iterations, the guidance should be on 'forcing' users choose long-enough passwords, not in this nitpicking over the 'right' # of iterations.

The number of iterations scales linearly with the cost of brute-forcing. The cost scales exponentially with the length of the password, assuming a random password (stops scaling when you reach the hash size I think). Both are important because you can't freely increase the password length, they become more annoying to enter and remember.

I never enter or remember any of the passwords bitwarden generates for me, I have an app and an extension for that.

Re: Bitwarden design flaw: Server side iterations

#26
post #20
post #16

Earlier quoted context omitted.

Even a fairly middling password manager implementation is better than just about any other strategy that anyone is likely to use. Especially because for the vast majority, the other strategy is going to be reusing the same password ~everywhere and if you're lucky the might use a special password for their bank or something.

I guess for most people online, writing all their passwords down in a notebook is more secure than using a password manager. It’s just less convenient.

And less resilient.

If your notebook is destroyed (e.g. dog eats it, fire, water damage, et al) then all your passwords are gone. With most good password managers you can actually backup and store a copy of your vault data locally.

Re: Bitwarden design flaw: Server side iterations

#28
post #3

If you think it's ok to be putting all your passwords on some random server owned by a random company then I don't know if you care about any other design flaws. This also includes the websites you visited and just happened to either accidentally or on purpose save your login. Now multiply the privacy/security implications of that when said company is pumped and dumped by a major VC.

[deleted]

Re: Bitwarden design flaw: Server side iterations

#29
post #11

Oof, my Bitwarden account was created a while ago and was set to only 5,000 iterations. You can see and change the number of iterations here: https://vault.bitwarden.com/#/settings/security/security-key... (or if you don't trust links for something like your password manager: log into your web vault, click on the top-right dropdown menu, then Account settings > Security > Keys). I've updated it to 600,000 iterations…

As of now, your link is fine (though the comment is probably still editable), and I believe you have the best of intetions but Note: It's not a great idea to click a link to something like Bitwarden, since a phishing domain could be used.

Re: Bitwarden design flaw: Server side iterations

#30
post #11

Oof, my Bitwarden account was created a while ago and was set to only 5,000 iterations. You can see and change the number of iterations here: https://vault.bitwarden.com/#/settings/security/security-key... (or if you don't trust links for something like your password manager: log into your web vault, click on the top-right dropdown menu, then Account settings > Security > Keys). I've updated it to 600,000 iterations…

I upped mine to more than 1M and haven’t seen any degradation of performance.
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