Details about the hacking algorithm A5 / 1

Late yesterday evening, information appeared that the German cryptologist Karsten Nohl (Karsten Nohl) demonstrated how to break 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 not a single hacker group has published full information about the hacking process, so the facts have not been confirmed. Now there was a public demonstration at the Chaos Communication Congress conference in Berlin. All information on the project hacking A5 / 1 published here . Tables for A5 / 1 codebooks can be found in torrents.

The Nola method makes it possible to reduce the GSM-cipher hacking time from several weeks to several hours, so that from now on the GSM interception is available not only to special services, but to any well-funded criminal organization. With the improvement of the method, the decryption time can be reduced to a few minutes.

Although security experts have long appealed to GSM operators to switch to 128-bit A5 / 3, this does not happen. The fact is that upgrading requires significant investment. Even now, representatives of the GSM Association commented on the report of Nol in the spirit that his work is illegal, and that hacking is possible only theoretically, but in fact it is almost impossible to use it.