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Time-memory tradeoff in SSL's RC4 code?



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>Date: Thu, 17 Aug 1995 08:32:56 -0400
>From: "Perry E. Metzger" <[email protected]>
>Subject: Re: SSL challenge -- broken !

>It has occured to me that, because the RC4 key crackers spend most of
>their time in key setup, you can crack N SSL sessions that you
>captured in not substantially more time than it took to crack 1. This
>is analagous to the way brute force Unix password file hacking operates.

This would work with straight 40-bit keys, but I believe SSL uses
128-bit keys, and then intentionally leaks 88 bits to comply with
export requirements, to prevent this kind of attack from working.

>Perry

   --John Kelsey, [email protected]
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