[Cfrg] Encrypting a known short text

"Erik Andersen" <era@x500.eu> Fri, 22 September 2017 16:19 UTC

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From: Erik Andersen <era@x500.eu>
To: Cfrg <cfrg@irtf.org>
Date: Fri, 22 Sep 2017 18:19:49 +0200
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Subject: [Cfrg] Encrypting a known short text
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Suppose we have a protocol, where everything is encrypted.


If the clear (short) text may be guessed by an attacker (it could be an
ASN.1 NULL), do we then have a security issue, where the encryption key
could be revealed? 


Best regard,