Old cell phones networks encryption were deliberately weakened
good thread that you must readMotherboard: A new academic paper found two old encryption algorithms still used in phone networks can be exploited to snoop on phone's internet traffic. GEA-1, the algorithm used when the phone industry adopted GPRS standards in 2G networks, was effectively backdoored that could allow the decryption of a phone user's traffic. One of the researchers said millions of users were poorly protected for years as a result of having to "meet political requirements." GEA-2, the succeeding algorithm, did not contain the same weaknesses. But GEA-1 is still baked into some phones as a fallback when there's only GPRS coverage in certain countries.
A new paper shows that two old encryption algorithms still used in mobile networks can be exploited to spy on phones' internet traffic.