openpgp dsa subliminal key reconstructor

Atom 'Smasher' atom at suspicious.org
Fri Aug 6 05:52:32 CEST 2004


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Hash: SHA256

On Wed, 4 Aug 2004, Werner Koch wrote:
> On Wed, 4 Aug 2004 01:56:06 -0400 (EDT), Atom 'Smasher' said:
>
>> http://www.aculei.net/~shardy/code/subdsakey.pl
>
> Where is the news?  It is a well understood property of the ElGamal
> signing scheme. You don't even need such a channel, you may also
> subvert the signing program to use the same value for k more than one
> time.  There are anyway uncounted ways to use subliminal channels to
> export private keys.
=============

not being math savvy, i knew it was possible, but i thought of it more in 
a theoretical sense... seeing it done within a few seconds on a laptop was 
very impressive.

morals of the story:
    1) verify the signatures of source code!
    2) roll your own binaries!
    3) run an IDS system!


  	...atom

  _________________________________________
  PGP key - http://atom.smasher.org/pgp.txt
  762A 3B98 A3C3 96C9 C6B7 582A B88D 52E4 D9F5 7808
  -------------------------------------------------

 	"If all the personal computers in the world - 260 million -
 	 were put to work on a single PGP-encrypted message, it
 	 would still take an estimated 12 million times the age of
 	 the universe, on average, to break a single message."
 		 -- William Crowell, Deputy Director,
 		National Security Agency, March 20, 1997
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.3.6 (FreeBSD)
Comment: What is this gibberish?
Comment: http://atom.smasher.org/links/#digital_signatures

iQEcBAEBCAAGBQJBEwCFAAoJEAx/d+cTpVciG/oH/jIC4eDcstmKNq4TYBRnjHGl
sgdPKTYyI741CLAUnbhvwhckfgkXH1ADGMivVptVABvTLGUgcgb4M78qTesoOg74
od03zeAo25KTU8cH+cCFbBovDjOO+ET9wyA6DBr3LVipRp0FjXkInN/PMIbV/Yfw
fd3HpW2mICFUkwkcD0J0xzeoWUAE4BNRZyoOo2dMKjzJ287Ybi7hQaB8oQ4rfSvD
W03s703hfHkm99mKpf9lnRHbevofD4CmbVZtxVKxP8baHqvoZh3dGXsr9FTnKfEq
3WdPKzpWaMAK9Qd/kq3UEoQoAMncU0VF2sKPFCJ5G09O1PiAjSkskt96QHpqJYE=
=7AzE
-----END PGP SIGNATURE-----



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