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A comment on Slack was hacked. Parent comment

Re:Slack was hacked by randunel on Friday March 27, 2015 @02:20PM (#9278118)
In your website's example, you have

    bcrypt(password, salt+pepper)
Observe the difference between that and the rehash you just posted

    bcrypt(bcrypt(password, salt), pepper)
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Re:Slack was hacked by mbrubeck on Friday March 27, 2015 @05:30PM (#9279141)
> bcrypt(password, salt+pepper)

I hope it's obvious that no one should never do this, since the output would contain the "salt+pepper" bits in cleartext alongside the hash, defeating the entire point of the "pepper":

https://www.usenix.org/legacy/event/usenix99/provos/provos_h...

In fact, this is a perfect illustration of why it's bad to put secret bits into a crypto function in a place that's not designed to take secret bits. Bcrypt does not treat the salt parameter as a cryptographic secret, and other algorithms might not either. And they might leak it in more subtle ways.

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Re:Slack was hacked by rmrfrmrf on Saturday March 28, 2015 @12:00PM (#9281823)
One would think it's obvious, yet this is what the person in the linked article suggests doing :/
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