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It's not so much "how long does it take" as it is "how much does it cost" and the answer to that really depends on what sort of compute infrastructure you have access to. Using a more appropriate hashing algorithm with a sufficient cost factor can massively increase the amount of compute needed. Preventing the re-use of that computational effort on additional users is why unique salts are important.


> It's not so much "how long does it take" as it is "how much does it cost"

So the answer is "It's too expensive to figure out in practice, unless you're being explicitly targetted by someone with nation state level credentials?", i.e. it's pretty much fine?

> Using a more appropriate hashing algorithm with a sufficient cost factor can massively increase the amount of compute needed.

But by the sounds of it, SHA1 is more than enough (given that nobody here is willing to brute force the hash I shared above?)

> Preventing the re-use of that computational effort on additional users is why unique salts are important.

The person who "cracked" my first hash found it in a list of passwords which was actually gotten from a plain text dump 15 years ago. That wasn't found by reversing a hash, so the compute wasn't reused. You are right that once it's cracked, it's cracked and that's that, but if your password _isn't_ cracked it's moot whether it's hashed with SHA1 or something more secure, as per above?


>But by the sounds of it, SHA1 is more than enough (given that nobody here is willing to brute force the hash I shared above?)

SHA1 is "more than enough" for this specific interaction in which you chose a complex password and/or your only opponents are unmotivated/non-incentivized HN commenters that don't have a password cracker at their immediate disposal. That doesn't mean anything outside of this context.

If your opponent was a motivated hacker with dedicated password cracking machines (which do not require anything even close to a nation-state budget, btw), your SHA1 hash would be much more likely to be cracked. If you were a specific target of a hacker group, such as an employee of a company that is being targeted by an attack or someone known to have a BTC wallet with $10 million in it, your SHA1 hash would be much more likely to be cracked. If your password was a relatively simple phrase like "dog$aregreat2019", like the vast majority of user passwords are, it would almost certainly be cracked.

SHA1 is not even anywhere close to "enough" for general password hashing use. Don't think otherwise just because a couple of random HNers failed your little game.

edit: The premise of your "challenge" is also not equivalent to the goals of most hackers. Unless you are a specifically known and prioritized target (because you're a celeb, VIP, wealthy person or something like that), the goal of a hacker is not to take one specific hash and crack it, because the success of that will depend a lot on the complexity of your password. The goal of most hackers in a breach like this Twitch one is more like "just throw it all at the wall and see what sticks". They take a massive database of thousands of hashes and spend a few hours to see what can be cracked, taking advantage of the fact that while some people may have complex passwords, most do not. After a few hours, maybe they crack 90% of the SHA1 hashes in a leak. Maybe your password was complex enough that it was in the 10% that wasn't cracked; good for you, but just because your password remained uncracked doesn't mean SHA1 is "enough". The hackers still got the other 90%.


But you shared a hash of an uncommon password. We probably have the salt (probably somewhere in the code) and people dont use password managers. So rainbow tables are enough. Oh, I thought the first sentence was you and not quoted. Agreed with the above


> But by the sounds of it, SHA1 is more than enough (given that nobody here is willing to brute force the hash I shared above?)

Absolutely not and that is a ridicoulous conclusion to draw. State-level resources are absolutely not required to break sha1.

> but if your password _isn't_ cracked it's moot whether it's hashed with SHA1 or something more secure, as per above?

Again, absolutely not. The algorithm and cost setting have a huge impact on the practical likihood that an attacker will crack your password.




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