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Slack was hacked

slackhq.com

121–130 of 526 posts

Re: Slack was hacked

#121
post #5
post #3

> No financial or payment information was accessed or compromised in this attack. This wouldn't be my first concern. It would be all of the confidential communication that happens within slack.

Agreed. The content of the chat's would be potentially much more important in my mind.

Maybe it's time for Slack to adopt the Axolotl ratchet, too.

Re: Slack was hacked

#122

Earlier quoted context omitted.

Not sure why this is being downvoted. Setting up IRC on a .onion isn't even difficult. Setting it up with SSL is only a touch harder.

Setting up an ircd is not a bad idea. Then we just need to find the ircd and client that does what Slack does. (Which is totally possible, but I'm not sure it exists?)

I am interested first in persistent backlogs -- do you know an IRCd that does that? I am sure it couldn't be implemented client-side.

I remember "SILC" which is not IRC, but if I remember correctly it had this. Mainly when you join a room, you should not get tabula rasa. You enter into some context, and if the last message was posted 4 days ago, your context starts 4 days ago, and the datestamps all reflect this.

There are other features of Slack that make it worth using, but this is the one thing I don't know if IRC can support at all, that I see every other serious chat system doing.

Re: Slack was hacked

#123

Earlier quoted context omitted.

If you get the user table, you can log in. If you can log in as (some) users. If you can do that, you can see (some) chat history. edit you can log in if and when you crack some of the hashes.

Incorrect. You can't login with a password hash, you need a password.

No kidding. That's why I put (some) users. Because brute-forcing the hashes will give you some password plain texts.

I guess that I missed a step in the explanation where you attack the hashes.

However I see that they say that they are using some best practices (bcrypt, "salt per-password") so this attack will be largely mitigated.

Re: Slack was hacked

#124

Earlier quoted context omitted.

If you get the user table, you can log in. If you can log in as (some) users. If you can do that, you can see (some) chat history. edit you can log in if and when you crack some of the hashes.

Incorrect. You can't login with a password hash, you need a password.

If you get the user table, you can crack the password hashes offline, at your leisure.

Re: Slack was hacked

#125

Earlier quoted context omitted.

My concern are the usernames, emails and phone numbers that were probably not encrypted

Exactly!!! Encrypting user data should be a common practice like hashing passwords.

Third party authentication should be the norm. Leaving authentication to providers that absolutely know their shit, just like we leave payments to third party services.

Of course, that requires a decent protocol, and Mozilla is doing the world a disservice in not marketing Persona better seeing as it's the right solution....

Re: Slack was hacked

#126

Literally was arguing with someone like two days ago that using Slack for sensitive data was a bad idea, guaranteed to blow up in your face sooner or later. Nothing sweeter than "I told you so".

given the use of bcrypt for password salt/hashing, I'd say any attacks from here may be targetted to specific users, or those with really weak passwords (top 10k password list) run through wouldn't take too long on a distributed cluster per user. How much that opens up, and how that corresponds or overlaps with slacks password requirements will vary.

Re: Slack was hacked

#127
post #83

Earlier quoted context omitted.

Why? Encrypting e-mail addresses would break password reset features and phone numbers are generally public anyway (yes you can go X-directory, but the real issue here is why these services require a valid phone number to begin with)

Why would encrypting email addresses break password reset? You can encrypt the database at rest such that the application has a private key that can decode it. That way both the application and the database server need to be breached to obtain anything usable.

Or just the application. Generally, it's much easier to convince apps to give you the data instead.

Re: Slack was hacked

#128
post #19

Host your own IRC if you care about the privacy and security of your communication. There is no reason why you can't take 10min to setup a IRC with SSL on your own. Yes, Slack is awesome, lots of features, but it's not yours!

Agree with you in one sense of being responsible for your own security, but by this logic I should keep all my money under the mattress instead of the bank, no?

Not the same thing. Banks are insured against robbery and theft, so if something like that happens, customers don't lose their money. In addition, there's an insane amount of fraud protection in the banking industry, and billions of dollars of vested interests to make sure criminals are caught and prosecuted.

Can you say the same about cloud services?

Re: Slack was hacked

#129
post #50

Assuming (no evidence, it's just very common) that this was a SQL Injection, here are some ways to protect yourself: * Use http://en.wikipedia.org/wiki/Database_activity_monitoring . If you don't list users on your site and you get a query that would return more than one user record, it's a hacker * Add some http://en.wikipedia.org/wiki/Honeytoken s to your user table, and sound the alarm if they leave your db * Use…

Why would you assume that? There are plenty of ways to hack into stuff without sql injections.

[deleted]

Re: Slack was hacked

#130
I hate to be the negative guy, and they were hashing passwords better than 90% of the sites, but it would be SO easy to completely neutralize password leakage when the attacker only has access to the database.

https://blog.filippo.io/salt-and-pepper/

tl;dr: Hardcode a second salt in your application code or in an environment variable. Then a database dump is not enough anymore to do any kind of bruteforce.

It's simple, free and you can retroactively apply it.

EDIT: I addressed some of the points raised in this thread here https://blog.filippo.io/salt-and-pepper/#editedtoaddanoteonr...

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