Researchers at a university in Germany have used open-source software to crack the encryption key for satellite telephones in about an hour.

The team bought two readily-available sat phones and downloaded firmware updates for them. The updates revealed the encryption on the sat phones was not much different from regular cell phone GSM encryption, which has been cracked in the past. From there, it did not take much to crack the sat phone encryption.

In some regions of the world standard cell phone communication is still not available. In war zones, developing countries and on the high seas, satellite phones are used instead. Here, the telephone is connected via radio directly to a satellite. This passes the incoming call to a station on the ground. From there, the call is fed into the public telephone network. So far this method was considered secure.

Encryption algorithms are implemented to protect the privacy of the user. There is, as yet, no alternative to the current standards. Since users cannot rely on their security against interception, similar to the security of standard cell phones, they will have to wait for the development of new technologies and standards, or make use of other means of communication for confidential calls.