In October 2024, the Wall Street Journal reported a large cyberattack against U.S. telecommunications companies. The FBI, NSA, and the Cybersecurity and Infrastructure Security Agency released new guidelines for protecting communications infrastructure in the United States. Despite the government’s efforts, the Chinese hackers continue their hacking of US telecom networks.
If the most valuable items on your phone are family photos, you probably do not need to worry about foreign hackers targeting you. But what if you text about national secrets, company secrets, or politically sensitive data? What if you simply want to ensure your messages are private?
Unencrypted text messaging
When officials say, “Stop sending text messages because they are not secure,” they are referring to the Short Message Service (SMS) and Multimedia Messaging Service (MMS). Not all text messages sent by phone are insecure. Here’s how to tell the difference:
On your iPhone’s iMessage app, if your messages appear in green bubbles instead of blue bubbles, then that message was sent using RCS or MMS/SMS instead of iMessage.
Basically, the green bubbles indicate your message is unencrypted.
On Android’s Google Messages app, text messages light blue in the SMS/MMS (unencrypted) state.
You can distinguish RCS messages and SMS messages by looking for typing indicators and read receipts.
Non-smart phones almost always use SMS or MMS; therefore, they’re almost always unencrypted.
Encrypted Messaging
In full end-to-end encryption, only the sender and receiver can read the message. Nobody else. It has been the default on WhatsApp since 2016. The good news for iPhone owners is if you see the blue bubble on iMessage, your message is end-to-end encrypted. This applies to group messages, too. End-to-end encrypted messaging is not as effortless for Android owners. For them, encryption is available in Google Messages if the senders and recipients all have the feature turned on.
When an iPhone user wants to send a message to an Android user (or vice versa), they’ll need to use a third-party app to get end-to-end encryption. WhatsApp or Signal are two popular – and free – options. These apps also encrypt voice calls.
Text messaging is not approved for protected or confidential data, unencrypted or encrypted. Review Recommended IT Services for Confidential or Protected Information for approved services to store, create, or transmit WashU Confidential or Protected information.
Further Reading
Yes, FBI Announced Texting Between iPhone and Android Is Not Secure | Snopes.com
Encryption | Office of Information Security | Washington University in St. Louis