Re: Cracking decrypted file when knowing partial contents

From: MikeyD (m_donaghy50_at_hotmail.com)
Date: 04/20/04 

Date: Tue, 20 Apr 2004 18:29:15 +0000

Adfa wrote:

> Would it be easier to crack an encrypted file if the cracker knew some of
> the contents of the file?

If you know that one part of ciphertext corresponds to a particular piece of
plaintext, that makes it a great deal easier to crack almost any symmetric
algorithm.
>
> For example, an encrypted MS Word file where the cracker knew
> word-for-word a few paragraphs of the document, but not necessarily the
> exact byte postions of those paragraphs in the file.

IIRC that wouldn't help much, unless he tried them in various positions.