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GnuPG is NOT vulnerable to -Get Your Hands Off My Laptop-

This is a note about an improved side-channel attack on old versions of
GnuPG. Daniel Genkin, Itamar Pipman, and Eran Tromer latest research on
side channel attacks is described in the paper

Get Your Hands Off My Laptop:
Physical Side-Channel Key-Extraction Attacks On PCs

They target an older version of GnuPG and come up with awesome results:

We demonstrate physical side-channel attacks on a popular software
implementation of RSA and ElGamal, running on laptop computers. Our
attacks use novel side channels, based on the observation that the
"ground" electric potential, in many computers, fluctuates in a
computation-dependent way. An attacker can measure this signal by
touching exposed metal on the computer's chassis with a plain wire, or
even with a bare hand. The signal can also be measured at the remote
end of Ethernet, VGA or USB cables.

Through suitable cryptanalysis and signal processing, we have
extracted 4096-bit RSA keys and 3072-bit ElGamal keys from laptops,
via each of these channels, as well as via power analysis and
electromagnetic probing. Despite the GHz-scale clock rate of the
laptops and numerous noise sources, the full attacks require a few
seconds of measurements using Medium Frequency signals (around 2 MHz),
or one hour using Low Frequency signals (up to 40 kHz).

See for more.

If your GnuPG version is up-to-date there is nothing you need to do!

As noted in the paper GnuPG 1.4.16 and later are not vulnerable to the
attack. GnuPG 2.x and Gpg4win 2.x are not vulnerable, either. However,
if you are still using a GnuPG version older than 1.4.16 you should
update to at least 1.4.16 but better to 1.4.18. Note that those version
numbers are for the generic GnuPG versions from Some Linux
distributions may have an older version but all major distributions have
applied respective security fixes back in December or January.

Watching out for possible security problems and working with researches
to fix them takes a lot of time. g10 Code GmbH, a German company owned
and headed by me, is bearing these costs. To help us carry on this
work, we need your support; please see .



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