RE: ADS Password Storage Protection



Jeff,

You response is a no go, maybe you are unaware of how the LM store works.

"garzelfloposaurus" there would be no LM hash of this password nor of my old
king passphrase example, because LM is limited to 14 characters.

That is where you are mixing up the getting the first half and guessing the
second.

If you did have the first, how would you guess what portion of the rhyme I
used, what punctuation I used, and how long the passphrase was?


Dave




-----Original Message-----
From: Jeffrey F. Bloss [mailto:jbloss@xxxxxxxxxxxxxxx]
Sent: Wednesday, July 19, 2006 14:51
To: security-basics@xxxxxxxxxxxxxxxxx
Subject: Re: ADS Password Storage Protection

dave kleiman wrote:

> Eric,
>
> I beg to differ.
>
> Are you suggesting that a 40-60 character passphrase
"&Old King Cole
> was a merry old soul, a merry old soul was he; he called
for his pipe,
> he called for his bowl!!" is not more secure than "$%Op13f987&"

In some ways yes, and in some ways no. :)

The essence of the LM Hash vulnerability is being able to
derive an entire pass phrase from a portion. Since pass
phrases were hashed in "chunks" it was possible to crack a
smaller chunk and potentially guess the rest from that
information. If you discovered the text "garzel" and knew a
pet's name was "garzelfloposaurus"... :)

Your Old King Cole example suffers from the same weakness.
It wouldn't take long to figure out the rest if we knew the
"&Old Ki" part. And of course "&Old Ki" is less secure than
"$%Op13f987&" in every way.

--
Hand crafted on 19 July, 2006 at 14:41:28 EDT

Does the name Pavlov ring a bell?



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