Cracking OSX Lion passwords

#1

Post by eis » Sun, Sep 18, 2011, 8:01 PM UTC

Cracking OSX Lion passwords
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Re: Cracking OSX Lion passwords

#2

Post by KonradKlause » Sun, Sep 18, 2011, 8:19 PM UTC

TL;DR:

There is no need to crack the password. You (as non-root user) can just reset the currently logged in user's password by calling:

dscl localhost -passwd /Search/Users/bob

Re: Cracking OSX Lion passwords

#3

Post by drivebyacct2 » Sun, Sep 18, 2011, 8:23 PM UTC

I suppose it's different if an unauthenticated user can perform a password change with the system powered on, but similar things can be done with Windows and a Linux live cd with some tools, and Linux passwords can be changed in "single user" mode.

Re: Cracking OSX Lion passwords

#4

Post by maximilian » Sun, Sep 18, 2011, 8:24 PM UTC

In the article, it mentions that the password are hashed using SHA-512. As has been mentioned before, using such a fast hashing scheme for passwords is a terrible idea. Any idea as to why they do it this way? (instead of using bcrypt)

Re: Cracking OSX Lion passwords

#5

Post by maximilian » Sun, Sep 18, 2011, 8:25 PM UTC

drivebyacct2 wrote: post #3

I suppose it's different if an unauthenticated user can perform a password change with the system powered on, but similar things can be done with Windows and a Linux live cd with some tools, and Linux passwords can be changed in "single user" mode.

You can also just pop in the OS X cd and change the password at boot.

Re: Cracking OSX Lion passwords

#6

Post by RyanKearney » Sun, Sep 18, 2011, 8:31 PM UTC

maximilian wrote: post #4

In the article, it mentions that the password are hashed using SHA-512. As has been mentioned before, using such a fast hashing scheme for passwords is a terrible idea. Any idea as to why they do it this way? (instead of using bcrypt)

Because it just works.

Re: Cracking OSX Lion passwords

#7

Post by num1 » Sun, Sep 18, 2011, 8:32 PM UTC

maximilian wrote: post #4

In the article, it mentions that the password are hashed using SHA-512. As has been mentioned before, using such a fast hashing scheme for passwords is a terrible idea. Any idea as to why they do it this way? (instead of using bcrypt)

You're using an apple product. When did they ever claim to be secure? Your life is easier, more magical, full of glass, and very fast! Security is... a little bit of whipped cream on top. So enjoy your gestures on that magic touchpad, don't worry about being safe.

(Sorry, I couldn't resist)

Re: Cracking OSX Lion passwords

#8

Post by rmc » Sun, Sep 18, 2011, 8:34 PM UTC

maximilian wrote: post #4

In the article, it mentions that the password are hashed using SHA-512. As has been mentioned before, using such a fast hashing scheme for passwords is a terrible idea. Any idea as to why they do it this way? (instead of using bcrypt)

It's bad, but it's not that bad. SHA is widely supported, and not that bad, yet.

Also this is protecting desktop computers, where cracking hashes is not a common security problem. Getting the machine stolen in starbucks is probably much more common for this type of machine.

Re: Cracking OSX Lion passwords

#9

Post by scott_s » Sun, Sep 18, 2011, 8:35 PM UTC

KonradKlause wrote: post #2

TL;DR: There is no need to crack the password. You (as non-root user) can just reset the currently logged in user's password by calling: dscl localhost -passwd /Search/Users/bob

Not any, but the currently logged-in user.

Re: Cracking OSX Lion passwords

#10

Post by KonradKlause » Sun, Sep 18, 2011, 8:39 PM UTC

scott_s wrote: post #9

KonradKlause wrote: post #2

TL;DR: There is no need to crack the password. You (as non-root user) can just reset the currently logged in user's password by calling: dscl localhost -passwd /Search/Users/bob

Not any , but the currently logged-in user.

Thanks for the clarification!