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[STDS-P1619] Applicability of recent attacks on AES-256 to IEEE 1619 modes

Hi Folks,

I'm sure you've all seen the recent news on cryptographic breaks of AES-256.  Bruce Schneier has some good blog posts that cover these attacks:
So this begs the question:  Are the IEEE P1619.x family of cryptographic modes affected by these results?

I believe that the general answer is 'no', but I'd like to hear from some cryptographers who have read the papers more closely to confirm this suspicion.  Let me know your thoughts.

The first result (from May 28, 2009) only applies to a small percentage of keys, and is basically eclipsed by the second result.

The second result (from June 28, 2009) essentially shows that it is possible to recover the full AES-256 key after 2^119 encryption operations with related keys.  In this model, the attacker can choose to encrypt or decrypt with different functions of the original key.  In theory this means that AES-256 is weaker than AES-128, but in practice 2^119 operations is beyond the computation ability of human kind.

The third result (from July 31, 2009) shows that reduced-round AES-256 is broken pretty badly.  However, this result does not apply to the full AES-256 with 14 rounds.

So far SISWG has standardized or is in the process of standardizing the following AES128/256 modes of operation:


--
Thanks!
-Matt

http://www.mavaball.net/
Cell: 303-717-2717