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>It's possible that this first leak was just to establish trust so they can random or auction password hashes later. Password hashes are relatively useless tho

>It's possible that this first leak was just to establish trust so they can random or auction password hashes later. Password hashes are relatively useless though? Once the leak is announced I imagine most of the big targets will rotate their credentials. Then the next thing you need to do is spend possibly thousands in CPU time bruteforcing bcrypt hashes. Then I'm not sure what you can even do with those. I'm not criminally creative but I imagine you could make more by abusing trust with payment processors or fraudulent invoices.

j_walter 5y ago
Relatively useless...but if even a few percent of people recycle passwords used for banking or crypto platforms it could be a profitable cache of data.
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 ago
  Pretty much this. If they gain one email/username password combination - they can use it elsewhere.
  - skeeks 5y ago
    I 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 ago
      You 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 ago
      You can still run those "top billion popular password" lists against properly salted/hashed passwords.
  - growt 5y ago
    If they are properly hashed and salted, they can not.
    - xorcist 5y ago
      The point here is that once you brute force the plaintext password, the same password might be used elsewhere.
      - mercurywells 5y ago
        What if you did something like hash(plaintext_pw+"twitchsalt") <browser> ---> <server> hash(browser_hash + db_salt)
        xorcist 5y ago
        The browser_hash is now the password.
        growt 5y ago
        If 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 ago
        Well, bear in mind, the hacker also has the exact code Twitch uses to salt it's hashes.
    - thaumasiotes 5y ago
      Password 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.
- twofornone 5y ago
  That'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 ago
    Yes, 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 ago
    In 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 ago
    If 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 ago
      Why does it matter if hashes are the same? That only tells you the passwords are the same.
      - deleted 5y ago
        [deleted]
      - mindwok 5y ago
        If 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.
errantspark 5y ago
A few things here. If you're the sort of person who runs a crypto mine, which I assume many of the people interested in breaking hashes are you have enough firepower at your disposal to at least perform a targeted attack on a few hashes with relative ease. Ideally that would be useless because things are properly salted and you don't know the salt, however with access to all of the source code as we have here I think it isn't as clear cut, as it may be possible to reverse out the salts as well. I'm not a cybersec guy so please take my speculation with a grain of salt.
- maccard 5y ago
  I've heard this before, and queried how feasible an attack would be, as people always talk about just how bad this is but yet I've _never_ heard of someone having an account compromised through this vector, and I'd like to know how feasible it really is. Here's the sha1 of an unsalted password b85ffa7dae2cbed04e7d3335f6ebc43c8a5764dd How long does it actually take in practice to break something like this? I would love it if someone could prove it to me.
  - jaredsohn 5y ago
    Is the password ncc1701e? I just googled it and found https://hashtoolkit.com/decrypt-sha1-hash/b85ffa7dae2cbed04e7d3335f6ebc43c8a5764dd https://hashtoolkit.com/decrypt-sha1-hash/b85ffa7dae2cbed04e... along with other results.
    - maccard 5y ago
      It is! I guess using a password from Google isn't the best idea, and kind of defeated the point of what I wanted to ask (if your password isn't already hashed online how long does it actually take to break a sha1 hash), but definitely proves the point. Can I try again? Sha1 e7b7cdf949007abe7e8a190ba8eae56c60018c1f
      - Behemoth66 5y ago
        Couldn’t find it in 1.4 Trillion combinations. Used rockyou.txt with dive.rule. Took me 6 minutes to try all 1.4 trillion passwords. So either you have a strong password or I messed something up. What is it? In theory if your password was weak enough to be on this list it would take on average 3 minutes to break it on a GTX 1080.

j_walter 5y ago

Relatively useless...but if even a few percent of people recycle passwords used for banking or crypto platforms it could be a profitable cache of data.

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 ago
Pretty much this. If they gain one email/username password combination - they can use it elsewhere.
- skeeks 5y ago
  I 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 ago
    You 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 ago
    You can still run those "top billion popular password" lists against properly salted/hashed passwords.
- growt 5y ago
  If they are properly hashed and salted, they can not.
  - xorcist 5y ago
    The point here is that once you brute force the plaintext password, the same password might be used elsewhere.
    - mercurywells 5y ago
      What if you did something like hash(plaintext_pw+"twitchsalt") <browser> ---> <server> hash(browser_hash + db_salt)
      - xorcist 5y ago
        The browser_hash is now the password.
      - growt 5y ago
        If 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 ago
        Well, bear in mind, the hacker also has the exact code Twitch uses to salt it's hashes.
  - thaumasiotes 5y ago
    Password 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.
twofornone 5y ago
That'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 ago
  Yes, 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 ago
  In 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 ago
  If 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 ago
    Why does it matter if hashes are the same? That only tells you the passwords are the same.
    - deleted 5y ago
      [deleted]
    - mindwok 5y ago
      If 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.

errantspark 5y ago

A few things here. If you're the sort of person who runs a crypto mine, which I assume many of the people interested in breaking hashes are you have enough firepower at your disposal to at least perform a targeted attack on a few hashes with relative ease. Ideally that would be useless because things are properly salted and you don't know the salt, however with access to all of the source code as we have here I think it isn't as clear cut, as it may be possible to reverse out the salts as well. I'm not a cybersec guy so please take my speculation with a grain of salt.

maccard 5y ago
I've heard this before, and queried how feasible an attack would be, as people always talk about just how bad this is but yet I've _never_ heard of someone having an account compromised through this vector, and I'd like to know how feasible it really is. Here's the sha1 of an unsalted password b85ffa7dae2cbed04e7d3335f6ebc43c8a5764dd How long does it actually take in practice to break something like this? I would love it if someone could prove it to me.
- jaredsohn 5y ago
  Is the password ncc1701e? I just googled it and found https://hashtoolkit.com/decrypt-sha1-hash/b85ffa7dae2cbed04e7d3335f6ebc43c8a5764dd https://hashtoolkit.com/decrypt-sha1-hash/b85ffa7dae2cbed04e... along with other results.
  - maccard 5y ago
    It is! I guess using a password from Google isn't the best idea, and kind of defeated the point of what I wanted to ask (if your password isn't already hashed online how long does it actually take to break a sha1 hash), but definitely proves the point. Can I try again? Sha1 e7b7cdf949007abe7e8a190ba8eae56c60018c1f
    - Behemoth66 5y ago
      Couldn’t find it in 1.4 Trillion combinations. Used rockyou.txt with dive.rule. Took me 6 minutes to try all 1.4 trillion passwords. So either you have a strong password or I messed something up. What is it? In theory if your password was weak enough to be on this list it would take on average 3 minutes to break it on a GTX 1080.