[e-privacy] [perry at piermont.com: Record a keyboard, reconstruct what was typed.]

[putro]

c'e' anche un articolo in italiano su punto informatico

----- Forwarded message from "Perry E. Metzger" <perry at piermont.com> -----

To: cryptography at metzdowd.com
Subject: Record a keyboard, reconstruct what was typed.
From: "Perry E. Metzger" <perry at piermont.com>
Date: Thu, 15 Sep 2005 10:12:39 -0400


Interesting new paper:

http://www.cs.berkeley.edu/~tygar/papers/Keyboard_Acoustic_Emanations_Revisited/preprint.pdf

   We examine the problem of keyboard acoustic emanations. We
   present a novel attack taking as input a 10-minute sound recording
   of a user typing English text using a keyboard, and then recovering
   up to 96% of typed characters. There is no need for a labeled
   training recording. Moreover the recognizer bootstrapped this way
   can even recognize random text such as passwords: In our experiments,
   90% of 5-character random passwords using only letters can
   be generated in fewer than 20 attempts by an adversary; 80% of 10-
   character passwords can be generated in fewer than 75 attempts.

   Our attack uses the statistical constraints of the underlying content,
   English language, to reconstruct text from sound recordings
   without any labeled training data. The attack uses a combination
   of standard machine learning and speech recognition techniques,
   including cepstrum features, Hidden Markov Models, linear classi-
   fication, and feedback-based incremental learning.



Perry

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-- 
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ciao

GPG/PGP key available on keyservers


Tutti dicono che sono un bastardo ma io non ci credo. (Bukowski)
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