Miller discovered the default passwords set on the battery at the factory to change the battery into unsealed mode and developed a method that let him permanently brick the battery as well as read and modify the entire firmware.
"You can read all the firmware, make changes to the code, do whatever you want. And those code changes will survive a reinstall of the OS, so you could imagine writing malware that could hide on the chip on the battery. You'd need a vulnerability in the OS or something that the battery could then attack, though," Miller said."
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