December 29, 2009 at 13:44Details on breaking the A5 / 1 algorithm
Late in the evening yesterday, information appeared that German cryptologist Karsten Nohl demonstrated a way to crack the 64-bit A5 / 1 algorithm, which is used in all GSM mobile communication systems. This encryption algorithm is already 21 years old, and recently there have been several statements about its compromise, but until today no hacker group has published full information about the hacking process, so the facts have not been confirmed. A public demonstration has now taken place at the Chaos Communication Congress in Berlin. All information on the A5 / 1 hacking project is published here . A5 / 1 codebook tables can be found in torrents.
The Nol method can reduce the time it takes to crack a GSM cipher from a few weeks to several hours, so that now GSM wiretapping is available not only to special services, but also to any well-funded criminal organization. With the improvement of the method, the decryption time can be reduced to several minutes.
Although security experts have long been calling on GSM operators to switch to the 128-bit A5 / 3, this does not happen. The fact is that an upgrade requires significant investment. Even now, representatives of the GSM Association commented on Nol’s report in the spirit that his work is illegal and that hacking is possible only theoretically, but in fact it’s practically impossible to use it.
The Nol method can reduce the time it takes to crack a GSM cipher from a few weeks to several hours, so that now GSM wiretapping is available not only to special services, but also to any well-funded criminal organization. With the improvement of the method, the decryption time can be reduced to several minutes.
Although security experts have long been calling on GSM operators to switch to the 128-bit A5 / 3, this does not happen. The fact is that an upgrade requires significant investment. Even now, representatives of the GSM Association commented on Nol’s report in the spirit that his work is illegal and that hacking is possible only theoretically, but in fact it’s practically impossible to use it.