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Slack was hacked

slackhq.com

191–200 of 526 posts

Re: Slack was hacked

#191

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.

Depends on the nuances of the system. If you can pass-the-hash, you can get in.

Re: Slack was hacked

#192

Looks like they require Google Authenticator or Duo Mobile app to do two-factor auth. I'm not interested. Why can't they be like Github and just send me a text message? I don't want a dependency on some other company's product to make Slack more secure.

Those are only two examples of apps that support TOTP[0]. TOTP is a standard with many implementing apps, including free and open source that will accomplish the same thing. The two apps listed on the website are just well known examples.

[0] http://en.wikipedia.org/wiki/Time-based_One-time_Password_Al...

Re: Slack was hacked

#193
post #79

Earlier quoted context omitted.

It's the most common vulnerability. https://www.owasp.org/index.php/Top_10_2013-A1-Injection

It's the most common vulnerability on the web . It's certainly not the most common vulnerability in projects built under popular non-php frameworks. Under that model, it's harder to create a situation where a SQL injection is possible than not. Edit: Slack's in PHP, I thought it was in RoR for some reason. Oops.

Slack is a web service written in PHP, so I'd say elchief's assumption is reasonable.

Re: Slack was hacked

#194
post #172

Earlier quoted context omitted.

I think this just goes to show exactly why these systems will become more commonplace. There are only so many security experts to go around. Having all the very best concentrated on a smaller set of services seems like it makes more sense than trying to get a security expert for every service.

I agree, but can't deny self-hosted means your security lapses see less fanfare, which has value to the biggest and most lumberingest risk-adverse organizations

not to mention: you can host a chat server in your company network, somewhat protected from random people on the internet, and your ops people should already be securing that from external intrusions anyway.

Re: Slack was hacked

#195

Looks like they require Google Authenticator or Duo Mobile app to do two-factor auth. I'm not interested. Why can't they be like Github and just send me a text message? I don't want a dependency on some other company's product to make Slack more secure.

I hate to break it to you but SMS is some other company's product. Google Authenticator is not a cloud service; it's simply an implementation of the TOTP RFC and there are others available if you hate Google so much that you don't trust a purely local app written by them.

Re: Slack was hacked

#196

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 simpl…

I generally disagree with hardcoded salts, you should assume everything is compromised in a successful attack. But I'm actually commenting here because I don't see how you can retroactively apply the second salt to a hashed string. Could you please elaborate or share a link? Later edit: I'm referring to your example in your link: salt = urandom(16) pepper = "oFMLjbFr2Bb3XR)aKKst@kBF}tHD9q" # or, getenv('PEPPER') hash…

I don't understand your issue with hardcoded salts. It essentially works the same way as an HMAC. It is some secret material that further complicates the attackers job...It doesn't mean they react to a successful attack in a different way.

After hashing the password he is storing the hash along with the users random salt, not retroactively applying the salt a second time.

Re: Slack was hacked

#197

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 simpl…

I generally disagree with hardcoded salts, you should assume everything is compromised in a successful attack. But I'm actually commenting here because I don't see how you can retroactively apply the second salt to a hashed string. Could you please elaborate or share a link? Later edit: I'm referring to your example in your link: salt = urandom(16) pepper = "oFMLjbFr2Bb3XR)aKKst@kBF}tHD9q" # or, getenv('PEPPER') hash…

In incident response you assume the worst, but in system design you try to minimize impact of common attacks like SQL injection.

There's nothing wrong with nesting algorithms (see the Facebook hash onion), so you can use the following scheme:

    bcrypt(bcrypt(password, salt), pepper)
And do a pass on all your database entries like

    bcrypt(old_hash, pepper)

Re: Slack was hacked

#199
post #139

Earlier quoted context omitted.

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

You never decrypt a password however. You only compare the hashed version of the claimed one to the stored hashed version, a one-way operation. What could you do with a one-way encrypted phone number? I'm not able to enter a phone hash to make a call.

Encryption isn't the same as hashing. Encryption is two-way.

The previous comment did make the encryption / hash distinction - though I can totally understand how his post might have been misread that he was recommending the same mechanisms for both sets of data.

Re: Slack was hacked

#200

Looks like they require Google Authenticator or Duo Mobile app to do two-factor auth. I'm not interested. Why can't they be like Github and just send me a text message? I don't want a dependency on some other company's product to make Slack more secure.

SMS is far more insecure than Google Authenticator. Also, you can use other apps like authy if you don't want to use Google Authenticator for whatever reason.
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