News Eight RTX 4090s Can Break Passwords in Under an Hour

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Can I ask a noob question about this? Wouldn't the system you're attempting to connect to stop accepting log in attempts after 3 fails? This was a problem for me logging into a work system after coming back after an extended vacation. I had to call into the help desk to unlock my account.
 
Can I ask a noob question about this? Wouldn't the system you're attempting to connect to stop accepting log in attempts after 3 fails? This was a problem for me logging into a work system after coming back after an extended vacation. I had to call into the help desk to unlock my account.
Generally, yes.

This article and method is talking about a list of passwords, saved locally and offline.
Not an online system or resource.
 
Can I ask a noob question about this? Wouldn't the system you're attempting to connect to stop accepting log in attempts after 3 fails? This was a problem for me logging into a work system after coming back after an extended vacation. I had to call into the help desk to unlock my account.
I would add that the concept of a hash is an important concept that was glossed over. Password hashing is defined as putting a password through a hashing algorithm to turn plaintext into an unintelligible series of numbers and letters. For example "MyPassword123" could have a hash value of "sy2x1396m2" The power of the hash is that it is meant to be a one way process: Easy to get the hash from the password, but (hopefully) extremely difficult to get the password from the hash. If you create a password for a website, then the website stores your hash and not your password. Not even the admins running the website can get your password from the hash. If someone gets your hash, then it (in theory) is worthless to them because they can't just type in the hash. When you type in your password, the website runs the hash process on what you typed and checks to see that the resulting hash matches the hash they have on file for your username. If the website is hacked and somebody gets a list of usernames and hashes this is ideally useless information because, as mentioned, they can't just type in the hash as a password. Now we get the the meat of the article: Someone can use a program such as HashCat to "reverse engineer" any hash that they stole and thus know your password. They can then go online and on the first attempt gain access to your account.
 
While it is cool almost all modern authentication systems lock you out after a given number of attempts or require a 2 factor of some sort. This won't mean much except for the rare occasion where you have full access to a system and need to hack into it because you yourself lost something.
 
It's NOT shocking that it's double the performance of the 3090!? how long has this guy been reviewing GPUs? it's one of the largest generation over generation performance increases ever!
 
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I'm curious how they managed to get 8 cards to work together. SLI is dead and given the sheer size of the 4090 there's no way you'd find a mainboard big enough to run more than 2 in a single machine.
Math. He measured 1x 4090 and multiplied by 8. Password cracking can spread the load across GPUs weather they are in the same system or across the world from each other. E.g. if your key space has 8 billions possibilies, 1 B are sent to each GPU. It does not require communication between GPUs during the cracking operation. Thats one reason why botnets with access to millions of computers are so dangerous.
 
So, EIGHT 4090s and 48 minutes to hack a lousy 8 character password .....

Question: How many 4090s and billion hours will take to hack a 30 character password (like the ones I use)????
 
Of course having a 3 tries and you're done for 24 hours would stop any bruteforce attacks trying to hack a password for that, but for anything without a timeout you need an especially complex password.
Just going to a 9th character means it would take 76 days to get the hash for all 9 character passwords using their 48 minutes for 8 character passwords. If you want to go to 10 characters that brings the time up to 20 years. Last year NIST went through and changed their recommendations for passwords. They were saying that length is more important than use of special characters. Don't force password changes after a certain time interval as that leads to password atrophy. If you are required to change your password every 90 days you will do something like Winter2020 then Spring2021, etc... Then they said 2FA, password managers, and pasting in of passwords is the best idea.
 
... What it does do, however, is to create a big mess for crypto/security in general. It used to be a pain to crack a secure encrypted connection. Now it is not. Random password or no, I can rerun your packet streams with different keys as many times and as fast as I want.

You think you get privacy with your VPN? Lol! No.
The article is talking about user passwords, so maybe up to 12 characters cracked with either a dictionary or brute force methods. Secure encrypted connections are 256 bit encrypted, so this method will crack the encryption in slightly less than 2.29*10^32 years.
 
"Additionally, the password-cracking ease of tools such as HashCat are usually deployed against offline assets, not online ones. This means that the chances of your PC being the target of a deranged RTX 4090-owner cracking passwords at will are slim — so slim they're almost nonexistent. "
Agree. However the article goes to great lengths to hide the fact that it is talking about offline cracking. Click bait anyone?
 
Can I ask a noob question about this? Wouldn't the system you're attempting to connect to stop accepting log in attempts after 3 fails? This was a problem for me logging into a work system after coming back after an extended vacation. I had to call into the help desk to unlock my account.
The article fails to make it clear it is cracking offline passwords. Like password protected zip files. Your online password is safe as long as the server locks you account after a few failed attempts.
 
Very good point about hashed passwords stolen from server password stores. However, it may be dependant on the hash function used. If the function uses a SHA-256 to hash the password, the sun may burn out before it is cracked. For MD5 hashing, 40 minutes would crack most passwords.
 
Does it, though?

From the article, second-to-last paragraph:
It literally says 'offline assets'. Online assets (a) lock themselves after a number if failed attempts. Try it yourself. (b) online asset crack attempts are over the internet, 1000's of times slower than cracking a password on a file on your local machine.