A backdoor in mobile phone encryption from the '90s still exists. The IT security experts received the GEA-1 and GEA-2 algorithms from a source who wishes to remain anonymous. Today, most data traffic is sent over the 4G network, also called LTE. Moreover, the data is now protected with additional transport encryption. Therefore, the researchers assume that the old vulnerabilities that still exist no longer pose a serious threat to users. Cryptanalysis of the GPRS Encryption Algorithms GEA-1 and GEA-2

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