Is it possible to safely check for certain characters in a password?
Is it possible to safely check for certain characters in a password?
Basic cyber security says that passwords should be encrypted and hashed, so that even the company storing them doesn't know what the password is. (When you log in, the site performs the same encrypting and hashing steps and compares the results) Otherwise if they are hacked, the attackers get access to all the passwords.
I've noticed a few companies ask for specific characters of my password to prove who I am (eg enter the 2nd and 9th character)
Is there any secure way that this could be happening? Or are the companies storing my password in plain text?
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I'm assuming they're plain text. There's is no perceivable way they can only use those data points to to figure out which hash it is. Unless of course they're using their own "hashing" function which isn't secure at all since it's probably reversible.
Theoretically they could take those two characters + a salt and then also store that hash. So there it is technically a way to do it although it'd be incredibly redundant, just ask for the actual password at that point.
Please don’t do that. Brute force attacks are very easy on single characters, even two of them.
Yes, I did a reply about this above because this idea has been suggested a few times and it's truly a bad security move. I'd prefer they just encrypted it and made sure the key was stored separate from the database. That's more secure than this idea.
Perhaps they validate the passwords client side before hashing. The user could bypass the restrictions pretty easily by modifying the JavaScript of the website, but the password would not be transmitted un-hashed.
It is worth pointing out that nearly any password restriction like this can be made ineffective by the user anyway. Most people who are asked to put a special character in the password just add a ! to the end. I think length is still a good validation though and it runs into the same issue @randombullet@lemmy.world is asking about
How would they validate individual characters client side? The set password is on the server.
When you are filling out the web form with your password it's stored plain text in the web browser and accessible via JavaScript. At that point, a JavaScript function checks the requirements like length and then does the salting/hashing/etc and sends the result to the server.
You could probably come up with a convoluted scheme to check requirements server side, but it would weaken the strength of the hash so I doubt anyone does it this way. The down side of the client side checking is that a tenacious user could bypass the password requirements by modifying the JavaScript. But they could also just choose a dumb password within the requirements so it doesn't matter much... "h4xor!h4xor!h4xor!" Fits most password requirements I have seen but is probably tried pretty quickly by password crackers.
OP asked about validating specific characters of the password. Commenter then said it has to be stored in plain text for that to work. Then you commented about client-side validation. Which I really don't see has anything to do with the stuff before in this thread?
Commenter said it has to be plain text server side. You implied validating client side would allow storing hashed passwords and still validating individual characters of the password. Which I asked how that would work. Your answer to that seems to give a general view of password handling on forms and validation?
They could hash the xth letters in a seperate column that are hashed separately, but it's likely they are just storing plain text.