From: "Deranged Mutant" <WlkngOwl@unix.asb.com>
Date: Thu, 1 Aug 1996 22:34:17 +0800
To: Bill Stewart <stewarts@ix.netcom.com>
Subject: Re: Cracking RC4/40 for massive wiretapps
Message-ID: <199608011151.HAA07754@unix.asb.com>
MIME-Version: 1.0
Content-Type: text/plain



Wait a minute: RC4 is an OFB cipher.  The previous plaintext has no 
effect on the ciphertext.  Hence, an attacker with shitloads of 
storage capacity can generate some initial output for each key and 
test each pre-stored key against ciphertext for possible hits.  Using 
'flaws' in the key schedule (esp. if the key is based on a password 
rather than a hash of a password) one could search for 'more likely 
keys' first.

Rob
---
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Key-ID: 5D3F2E99 1996/04/22 wlkngowl@unix.asb.com (root@magneto)
Send a message with the subject "send pgp-key" for a copy of my key.