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

November 10, 2023 by Jonathan Bennett 7 Comments

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” →

A small round NRF51822 board glued to the underside of a mailbox lid, with a small vibration sensor attached

Check Your Mailbox Using The AirTag Infrastructure

May 30, 2022 by Arya Voronova 32 Comments

When a company creates an infrastructure of devices, we sometimes subvert this infrastructure and use it to solve tricky problems. For example, here’s a question that many a hacker has pondered – how do you detect when someone puts mail into your mailbox? Depending on the availability of power and wireless/wired connectivity options, this problem can range from “very easy” to “impractical to solve”. [dakhnod] just made this problem trivial for the vast majority of hackers, with the FakeTag project – piggybacking off the Apple’s AirTag infrastructure.

This project uses a cheap generic CR2032-powered NRF51822 board, sending the mailbox status over the FindMy system Apple has built for the AirTag devices. For the incoming mail detection, he uses a simple vibration sensor, glued to the flap lid – we imagine that, for flap-less mailboxes, an optical sensor or a different kind of mechanical sensor could be used instead. Every time someone with a FindMy-friendly iPhone passes by [dakhnod]’s mailbox, he gets an update on its status, with a counter of times the sensor has been triggered. [dakhnod] estimates that the device could run for up to a year on a single battery.

Continue reading “Check Your Mailbox Using The AirTag Infrastructure” →

Get Apple To Track Your Bluetooth Devices For You

March 5, 2021 by Tom Nardi 10 Comments

Apple’s “Find My” service allows users to track their missing devices by leveraging a worldwide network of location-aware iGadgets. With millions of iPhones and Macs out in the wild listening for the missing device’s Bluetooth advertisements and relaying their findings to the Cupertino Mothership, it’s a highly effective way of tracking hardware so long as it stays in relatively urban areas. Unfortunately, the system is completely proprietary and non-Apple devices aren’t invited to play.

Or at least, that used to be the case. A project recently released by the [Secure Mobile Networking Lab] called OpenHaystack demonstrates how generic devices can utilize Apple’s Find My network by mimicking the appropriate Bluetooth Low Energy (BLE) broadcasts. Currently they have a firmware image for the BBC micro:bit, as well as a Python script for Linux, that will allow you to spin up an impromptu Find My target. But the team has also published all the information required to implement similar functionality on other BLE-capable devices and microcontrollers, so expect the list of supported hardware to grow shortly.

Somewhat ironically, while OpenHaystack allows you to track non-Apple devices on the Find Me tracking network, you will need a Mac computer to actually see where your device is. The team’s software requires a computer running macOS 11 (Big Sur) to run, and judging by the fact it integrates with Apple Mail to pull the tracking data through a private API, we’re going to assume this isn’t something that can easily be recreated in a platform-agnostic way. Beyond the occasional Hackintosh that might sneak in there, it looks like Tim Cook might have the last laugh after all.

It’s not immediately clear how difficult it will be for Apple to close this loophole, but the talk of utilizing a private API makes us think there might be a built-in time limit on how long this project will be viable. After all, Big Tech doesn’t generally approve of us peons poking around inside their machinations for long. Though even if Apple finds a way to block OpenHaystack, it’s expected the company will be releasing “AirTags” sometime this year which will allow users to track whatever objects they like through the system.