This Week In Security: Find My Keylogger, Zephyr, And Active Exploitation

Keyloggers. Such a simple concept — you secretly record all the characters typed on a keyboard, and sort through it later for interesting data. That keyboard sniffer could be done in software, but a really sneaky approach is to implement the keylogger in hardware. Hardware keyloggers present a unique problem. How do you get the data back to whoever’s listening? One creative solution is to use Apple’s “Find My” tracking system. And if that link won’t let you read the story, a creative solution for that issue is to load the page with javascript disabled.

This is based on earlier work from [Fabian Bräunlein], dubbed “Send My”. As an aside, this is the worst naming paradigm, and Apple should feel bad for it. At the heart of this cleverness is the fact that Apple used the standard Bluetooth Low Energy (BLE) radio protocol, and any BLE device can act like an Apple AirTag. Bits can be encoded into the reported public key of the fake AirTag, and the receiving side can do a lookup for the possible keys.

A fake AirTag keylogger manages to transfer 26 characters per second over the “Find My” system, enough to keep up with even the fastest of typists, given that no keyboard is in use all the time. Apple has rolled out anti-tracking protections, and the rolling key used to transmit data also happens to completely defeat those protections. Continue reading “This Week In Security: Find My Keylogger, Zephyr, And Active Exploitation”