4 ms·
>Then I'm not sure what you can even do with those Assume some end users used the same passwords on other, non-twitch accounts. That's what makes hacked passw
by tyingq 5y ago
>Then I'm not sure what you can even do with those
Assume some end users used the same passwords on other, non-twitch accounts. That's what makes hacked passwords valuable, no matter where they came from.
- axpy906 5y agoPretty much this. If they gain one email/username password combination - they can use it elsewhere.
- skeeks 5y agoI would be very deeply concerned if Twitch, a multi-billion dollar company owned by Amazon, does not properly hash and salt the passwords of its users.
- isbvhodnvemrwvn 5y agoYou don't brute force it, you find the password for accounts with the same e-mail in leaks from other sites and try only those.
- tyingq 5y agoYou can still run those "top billion popular password" lists against properly salted/hashed passwords.
- growt 5y agoIf they are properly hashed and salted, they can not.
- xorcist 5y agoThe point here is that once you brute force the plaintext password, the same password might be used elsewhere.
- mercurywells 5y agoWhat if you did something like hash(plaintext_pw+"twitchsalt") <browser> ---> <server> hash(browser_hash + db_salt)
- xorcist 5y agoThe browser_hash is now the password.
- growt 5y agoIf I understand this right, the problem is "twitchsalt" has to be known so that you can generate the same hash for future logins. So it's just one iteration of hashing more for a brute force attempt (modern hashing algorithms already use multiple iterations of hashing to make brute forcing harder)
- ocdtrekkie 5y agoWell, bear in mind, the hacker also has the exact code Twitch uses to salt it's hashes.
- thaumasiotes 5y agoPassword salting has nothing to do with password reuse. Imagine two people have accounts on each of two websites: eBay YouTube Alice sunlight bobrules Bob bobrules bobrules A password reuse attack dumps the YouTube database, cracks Bob's password, and then accesses Bob's eBay account. The fix for this is that Bob should use different passwords on his different accounts. Hashing helps by making step 2 ("crack Bob's password") more difficult. Salting does not affect this attack in any way. Note that the attacker didn't bother to dump the eBay database. The attack that salting protects against dumps the YouTube database, cracks Bob's password, and then accesses Alice's YouTube account.
- growt 5y ago"Salting does not affect this attack in any way." Yes it does. If you habe unsalted passwords you can just use a rainbow table to look passwords up.
- thaumasiotes 5y agoAnd that is not affected by salting. You can use a rainbow table to look passwords up whether or not those passwords are salted. There is zero conceptual connection between the two ideas. Now, realistically, you can't use a rainbow table on passwords of any noticeable length, and a salt may push the password over the edge of that threshold. If that's really what you want... enforce a minimum password length.
- growt 5y ago"Use of a key derivation that employs a salt makes this attack infeasible." https://en.wikipedia.org/wiki/Rainbow_table https://en.wikipedia.org/wiki/Rainbow_table "Salts defend against attacks that use precomputed tables (e.g. rainbow tables)" https://en.wikipedia.org/wiki/Salt_(cryptography) https://en.wikipedia.org/wiki/Salt_(cryptography)
- tyingq 5y ago
- twofornone 5y agoThat's something I've wondered - do password hashes tend to be the same across platforms? Is everyone using the same hashing algorithm? Isn't this also what salting is for? Never implemented auth myself.
- tyingq 5y agoYes, the hashes are (usually) different due to different algorithms and/or salts. But, if you've brute forced one by using good guesses, and know the email/userid for other sites, and the user used the same or a similar password...that doesn't matter.
- bduerst 5y agoIn a perfect world, no, but lazily someone could skip salting and/or use common hashing functions. IIRC this was a problem at Sony not too long ago.
- franga2000 5y agoIf everyone did things the way they're supposed to then no, hashes should never be the same between platforms. Using the same algorithm is likely, but as you said, salting solves that. But mistakes such as salting with just the username are sometimes made even by very large companies and in that case, hashes could be the same.
- evandwight 5y agoWhy does it matter if hashes are the same? That only tells you the passwords are the same.
- deleted 5y ago[deleted]
- mindwok 5y agoIf they are the same everywhere, you can precompute a huge database of hashes (called a rainbow table) and simply lookup the hash in the table when breaches occur to find the password. By salting, every provider who stores credentials has different hashes for the same inputs which makes the approach far less attractive at a large scale.