The Electronic Frontier Foundation is celebrating Google’s addition of a 2G kill switch to Android 12. The digital rights group has been campaigning against the outdated, insecure 2G cellular standard since 2020, and Android is the first mobile operating system to adopt the group’s advice. and users completely disable 2G.
In the US, carriers shut down 2G years ago and the 3G shutdown is already underway. Phones haven’t really gotten the message though, and modems are still trying to connect to nearby 2G signals automatically. The problem is, 2G is very old and a lot like connecting to a WEP-secured Wi-Fi hotspot: the security is outdated, so it’s easy to crack. If you’re in a country where the legitimate use of 2G has long since ceased to exist, the standard only serves as an attack vector via fake cell phone towers, so why not just disable it?
The EFF explains the issues:
There are two major problems with 2G. First, it uses weak encryption between the tower and the device that can be cracked in real time by an attacker to intercept calls or text messages. In fact, the attacker can do this passively without ever sending a single packet. The second problem with 2G is that there is no tower authentication on the phone meaning anyone can seamlessly imitate a real 2G tower and a phone using the 2G protocol will never be the wiser.
This is not to say that non-2G signals are ‘safe’. they are less insecure, but you still should not trust the mobile network. The best method is to encrypt everything. This is generally the default for web communications, but depending on how your carrier and phone are set up, carrier services like SMS and phone calls can be more vulnerable.
So why is 2G still enabled by default, even though it’s so obviously outdated? The 2G story varies wildly around the world. The IoT mobile company EMnify maintains an incredible global 2G phase-out list that is worth checking out. Some countries like the US, Canada, Japan, South Korea and Taiwan have been out of 2G for a while. However, Europe won’t kill 2G until 2025. Some South American countries will keep the standard until 2024, and some countries in Africa have no planned 2G shutdown date at all.
Even if you’re in a country that still has 2G, you’ll probably want to turn it off. 2G has no ability to transmit data at all, so it most likely only facilitates horrible analog voice calls and maybe SMS – if your carrier has the worst, most poorly maintained SMS system on the planet. Chances are, turning off 2G won’t change your smartphone experience at all, so give it a try.
With Android settled, the EFF is now targeting Apple. It is leading a Twitter campaign with a tweet with one click “Hey @Apple, 2G is an outdated and insecure technology! Google just gave us the option to disable it in our phones and now it’s your turn!”
How the 2G kill switch works on Android
This 2G kill switch is a new feature in Android 12, but which phones are actually getting it? As usual with Android, the answer is complicated and the move won’t come to all Android 12 phones. As the Android 12 release notes indicate, the actual requirements for the features are Android 12 and the “Radio 1.6 HAL”.
This radio “hardware abstraction layer” is one of the Project Treble vendor interfaces we talk about so often. Treble is a project that makes the operating system modular, away from the hardware support, making updates easier; this HAL is that interface between the operating system and the hardware driver. The actual HALs don’t get updated much, so your best bet is to get a 2G kill switch by buying a new Android phone that will launch with Android 12, not a phone that will be upgraded to Android 12.
But wait, this is Android, so the carriers can get in the way too. As the release notes say, “Carriers can disable the feature at runtime.” With all the possible variables here, the only way to really know if 2G killing is supported is to open the settings and take a look. I can confirm the switch is on the Pixel 6, and the EFF says to check out some newer Samsung phones.
If you want to disable 2G and have a normal settings layout, the switch is at “Settings > Network & Internet > SIMs > Allow 2G”. If your OEM has encrypted the Android settings for “differentiation” purposes, try searching for “2G” or search the cellular settings.