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Blizzard Network Breached; Change Your Battle.Net Passwords

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Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#111

Post by Digitalxero »

elithrar wrote: post #72
Digitalxero wrote: post #66

So I went to update my password for my World of Warcraft account after I saw this. And guess what I discovered, my current password is more secure than their current password policy will allow. So I filled out a support ticket with the following question (which all Blizzard account holders should ask them) I was wondering why even after you discovered a security breach you have not updated your password policy to act…

> "The only reason to have those two rules is because you are storing the password in plain text so anyone who gets access to the database can read them freely." That is certainly not the only reason to have those rules; in fact, it's probably one of the least popular reasons. It's done to keep customers creating short-ish passwords, which are likely to be more memorable, and therefore reduce the support load for pas…

they have a "I am an idiot and forgot my password" button so people forgetting their passwords is no additional support, and if they allow longer password it actually makes them easier for people to remember and harder to crack, win win.

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#112

Post by mindslight »

zaroth wrote: post #94

SRP is great at many things, but terrible at securing the server-side password database from brute force attacks. A quick look at http://srp.stanford.edu/design.html and http://srp.stanford.edu/demo/demo.html and you can see that SRP uses simple SHA1 plus a Salt to store the hashed passwords. With the hashes and salts stolen, please assume your password has been brute forced by the attacker (1 billion hashes per seco…

I haven't studied SRP, but a quick look at it and it seems that one also needs to perform the v = g^x. While still vulnerable to brute forcing due to lack of entropy in a password, this is more expensive than bare SHA1. The opine.me post you linked elsewhere completely glosses this over.

edit: okay, just to give you some very rough numbers from 'openssl speed' on my machine. 16 byte SHA1 is about 1M/sec. Projected dsa256 (based on dsa512 and its ratio to dsa1024) signatures (most of which is an exponentiation) is about 3k/sec. It's certainly not a purpose-built tunable KDF, but it's orders of magnitude harder than SHA1.

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#113

Post by zaroth »

Strilanc wrote: post #109
zaroth wrote: post #94

SRP is great at many things, but terrible at securing the server-side password database from brute force attacks. A quick look at http://srp.stanford.edu/design.html and http://srp.stanford.edu/demo/demo.html and you can see that SRP uses simple SHA1 plus a Salt to store the hashed passwords. With the hashes and salts stolen, please assume your password has been brute forced by the attacker (1 billion hashes per seco…

They use SHA1, although they make a couple of tweaks. I've implemented the bnet login stuff ( https://github.com/Strilanc/Tinker/blob/master/Bnet/ClientCr... ).

Well that's it then. 'g' and 'N' are published in your code, and they are using SHA1 as the hash.

GAME OVER. These passwords are cracked. Please see full explanation here: https://news.ycombinator.com/item?id=4364826

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#114

Post by zaroth »

thechut wrote: post #99
zaroth wrote: post #94

SRP is great at many things, but terrible at securing the server-side password database from brute force attacks. A quick look at http://srp.stanford.edu/design.html and http://srp.stanford.edu/demo/demo.html and you can see that SRP uses simple SHA1 plus a Salt to store the hashed passwords. With the hashes and salts stolen, please assume your password has been brute forced by the attacker (1 billion hashes per seco…

SRP is supposed to make use of multiple types of entropy to ensure the passwords are far more complicated that salted SHA1. While I agree it's possible that the attackers also got this information but I don't think we can jump to conclusions about the overall security of the passwords until more information is known.

Please read the RFC, it's right here: http://www.ietf.org/rfc/rfc2945.txt

Password entries are generated as follows:

         = random()
        x = SHA( | SHA( | ":" | ))
         = v = g^x % N

   G = 47
   N = 112624315653284427036559548610503669920632123929604336254260115573677366691719
What was stolen was no better than LinkedIn hashes -- for the purposes of dictionary attacking the database

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#115

Post by zaroth »

mindslight wrote: post #112
zaroth wrote: post #94

SRP is great at many things, but terrible at securing the server-side password database from brute force attacks. A quick look at http://srp.stanford.edu/design.html and http://srp.stanford.edu/demo/demo.html and you can see that SRP uses simple SHA1 plus a Salt to store the hashed passwords. With the hashes and salts stolen, please assume your password has been brute forced by the attacker (1 billion hashes per seco…

I haven't studied SRP, but a quick look at it and it seems that one also needs to perform the v = g^x. While still vulnerable to brute forcing due to lack of entropy in a password, this is more expensive than bare SHA1. The opine.me post you linked elsewhere completely glosses this over. edit: okay, just to give you some very rough numbers from 'openssl speed' on my machine. 16 byte SHA1 is about 1M/sec. Projected ds…

See below, the algorithm is clearly specified in the RFC, and it's no better than plain SHA1 in terms of preventing dictionary attacks once the database is stolen.

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#116

Post by harshreality »

Smerity wrote: post #97
DigitalSea wrote: post #79

Earlier quoted context omitted.

I didn't say that at all. I said it's easy to break into a bank but getting into a vault in this day and age is impossible. And if you somehow by luck or knowledge get into the vault there are secondary, third, etc security procedures in place such as alarms, self-locking doors, cameras and heat/movement detectors. A database is a vault. It's for storing things you don't want anyone to be able to access and even if a…

Bank vaults versus databases are entirely different. A bank vault can be locked down. It's only accessible for a small set of hours per day and access is only given to a small number of people. People also don't need random access to a bank vault. Website databases are more like cash registers. They need to be accessible 24/7 and nearly every transaction requires accessing it. Any person off the street is allowed int…

Brainstorm:

A major site storing authentication data should store it in a separate physical server, isolate that machine so that administrative access is not possible from the net (NO path from the net through to ssh or console server access to the auth server should be possible... that includes internet -> internal employee machine -> auth storage server). NAT and firewalls are irrelevant, because they do not protect against incoming attacks through tunnels initiated inside.

That may mean physical console only login access, if the general internal network has internet access. That's a necessary usability trade-off something as serious as an authentication database for ten million paying customers.

The authentication protocol to talk to the auth server should only allow simple (easily parsed) requests; they should be rate-limited, there should be no provision to check multiple hashes at a time, and it should be impossible to export hashes out of the auth server without administrative (console) access.

Similarly prudent precautions can be taken for backups of the auth data. The backup server encrypts the auth database, before writing it to an attached disk or whatever the scheme is. Several high-level employees then have usb keys with asymmetric keys, any of which (or any n of which) will decrypt the backups.

You can't air gap the auth server, but you can limit the attack surface so dramatically that you have a high degree of assurance that it's secure against network attacks aimed at authentication data disclosure.

Someone can own the webservers and collect passwords and one time auth tokens, and can compromise 2-factor seeds for users who are just setting up 2-factor, but that's far more limited than gaining access to hashes or seeds from auth servers.

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#117

Post by duaneb »

dhimes wrote: post #78
Steko wrote: post #63

Earlier quoted context omitted.

I think the bigger point is that a ton of signups use this question. Whether you say 'Mr. Smith' or 'Pecan Pie' isn't going to save you if you use it for all of them.

Actually, you often get to pick your question. If they don't hash the answer, however, you're screwed. It seems doable to me: drop on non alphanumeric (or something), split on whitespace, trim, lowercase, put back together. It beats the hell out of putting in the "right," googleable, answer. Sarah Palin can attest to that.

The only company I use that allows me to pick my security question is google. Apple doesn't, my bank definitely doesnt.

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#119

Post by Steko »

DigitalSea wrote: post #79
Steko wrote: post #70

Earlier quoted context omitted.

Did you really just insinuate that banks never get robbed?

I didn't say that at all. I said it's easy to break into a bank but getting into a vault in this day and age is impossible. And if you somehow by luck or knowledge get into the vault there are secondary, third, etc security procedures in place such as alarms, self-locking doors, cameras and heat/movement detectors. A database is a vault. It's for storing things you don't want anyone to be able to access and even if a…

"I didn't say that at all. I said it's easy to break into a bank but getting into a vault in this day and age is impossible."

Robbing bank vaults may be rare but it still happens.

Re: Blizzard Network Breached; Change Your Battle.Net Passwords

#120

Post by [deleted] »

zaroth wrote: post #114
thechut wrote: post #99

Earlier quoted context omitted.

SRP is supposed to make use of multiple types of entropy to ensure the passwords are far more complicated that salted SHA1. While I agree it's possible that the attackers also got this information but I don't think we can jump to conclusions about the overall security of the passwords until more information is known.

Please read the RFC, it's right here: http://www.ietf.org/rfc/rfc2945.txt Password entries are generated as follows: = random() x = SHA( | SHA( | ":" | )) = v = g^x % N G = 47 N = 112624315653284427036559548610503669920632123929604336254260115573677366691719 What was stolen was no better than LinkedIn hashes -- for the purposes of dictionary attacking the database

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