Apple’s in-house C1 modem can be updated along with the iOS 18.5 software.
iOS 18.5 debuted recently and came with several improvements and security fixes. The update also came with a security fix, notably a baseband flaw. Specifically, the patch was made to address the flaw, which allows an attacker to intercept and collect network traffic. Hackers could exploit it for surveillance purposes once they get into the cellular network infrastructure. Apple’s C1 modem handles signal processing for data, text, and calls between networks and devices, so it poses a significant risk.

Other than the C1 modem update, iOS 18.5 comes with other improvements, including vulnerabilities in WebKit, ProRes, Notes, FaceTime, file parsing, Bluetooth, call history, and image processing. iPhone owners are encouraged to get the update as soon as they can by going into their device settings and to Software Update. The device has to be charged and connected to the internet as well.