Security firm H4RDW4RE from
California aims to crack the A5/1 encryption
standard that is used to secure GSM traffic
from eavesdropping.

(Nota Editorial: Cryptophone
is not affected by this crack and at least now
everybody knows why to have a Cryptophone.
Anyway, we expect a GSM codebreaker with
published function to come along within
weeks. Other professional equipments
then will have a serious problem.
Cryptophone not.)

(2nd. Nota Editorial: It happend today, 29.12.09, pls see
http://cryptophones.info/_cms/article.php?story=20091229105953781)


As it stands right now, the A5/1 cipher is based
on a 64-bit key, which means each handset comes
with a 64-bit secret key that is known by the
connected GSM network. Each call initiated
over the GSM network will rely on the secret
key to generate a session key and encrypt
said phone call. H4RDW4RE aims to crack
this session key through the use of a
compressed and custom version of the
A5/1’s 128-petabyte code book, which
has been compressed to an impressive 2
or 3TB of data.

Source:Übergizmo
http://www.ubergizmo.com/15/archives/2009/12/h4rdw4re_to_crack_gsm_encryption.html