Cracking GSM

Cracking GSM with Software Defined RadioDid you ever think that your GSM phone calls are encrypted and can’t be monitored? Well, unfortunately GSM has been cracked. Last week Steve Gibson explained in his weekly Podcast Security Now! how GSM can be cracked.

It’s not as easy as listening to your neigbours conversation with a handheld scanner, but a software defined radio and the right application will enable you to listen to GSM conversations.

Those software defined Radios are not expensive anymore. Gibson refers in his Podcast to Ettus and the well known GNU-Radio, both hardware platforms available for a view hundred USD.

The main weakness of GSM is it’s old fashioned encryption. GSM is basically only XORing the binary data stream with a key. Being designed almost 20 years ago, hardware performance was very limited and it was almost impossible to re-engineer the crypto key. Today an off the shelve PC will do the job. All you need are a few terrabyte of harddisk to store the rainbow tables.

If you speak German, you will be able to listen to a Podcast of the famous Chaos Computer Club (CCC) episode they dedicated to GSM vulnerabilities.

Are you interested in the software? Here is the link to the GSM software project and the OpenBTS project. All free, all open source.

About Tobias (DH1TW)

Self-confessed Starbucks addict. Loves to travel around the globe. Enjoys the technical preparations of Amateur-Radio contests as much as the contests themselves. Engineer by nature. Entrepreneur. For more, follow him @DH1TW

Speak Your Mind