"Satellite phone communications can be decrypted in near real-time"

Two researchers from China have discovered the possibility of decrypting satellite phone communications that use GMR-2 cipher for encryption. The GMR-2 is a stream cipher that consists of a process in which keystreams are generated and ciphertexts are attained by the XOR of generated keystreams with plaintexts. In order to resist a plaintext attack, the encryption-key from the keystream must be protected by increasing the complexity of deriving it with an inversion attack. The researchers were able to perform an inversion attack against GMR-2, which allowed the real-time decryption of targeted communications. This article further discusses the GMR-2 cipher, how researchers made their discovery, and what other research concluded about GMR-2 cipher. 

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