Reverse Engineering on the GMR-2 standard: Two Chinese researchers have developed a method for decrypting satellite phone communications that works almost instantly and provides real-time access to third-party secure conversations.
Their method appears to present no problems against GMR-2, the latest version of GEO-Mobile Radio Interface used to support telephone satellite communications with airborne satellites.
GMR-2 encrypts all data sent from the user's phone to the satellite via an 64 bit key.
The new attack on GMR-2 is much faster than the previous one
In previous research papers, the 2012 and 2013, a group of five researchers from the Ruhr University in Bochum, Germany, developed an attack against encryption of satellite phones using the GMR-2 standard for communications security.
The German team's research described the first attack on the GMR-2 pattern, but it was complicated and difficult to perform in everyday life as it required time to calculate all the mathematical equations required for recovery of the encryption key used to secure the satellite phone communications.
In a paper (PDF) published last week, two Chinese researchers from the National University of Defense Technology in Changsha, China, describe a new attack against GMR-2 encryption, which can be carried out in a fraction of a second, allowing an attacker to obtain the encryption key instantly.
Reverse Engineering in GMR-2 encryption
The Chinese researchers report that their method is different from the one developed by the German team. Instead of trying to perform "plaintext attacks" on the encryption key through the "read-collision" and "guess-and-determine" methods, the Chinese team reverse engineered the entire procedure which follows a phone to choose an encryption key.
The fact allowed researchers to design an accurate system for identifying the encryption key used by a satellite phone to encrypt its data by examining the already encrypted data sent by the phone.
Although we are currently talking about academic and scientific success, this research can have disastrous results, as this new attack could be used to monitor satellite telephone communications.
Satellite telephones are vital equipment, often used in wars, by secret agents, activists, dissidents, and many others.
