Raspberry Pi 3 Model B+

The ARM-based hardware debugging feature on Raspberry Pi 3 module B+ and possibly other devices allows non-secure EL1 code to read/write any EL3 (the highest privilege level in ARMv8) memory/register via inter-processor debugging. With a debug host processor A running in non-secure EL1 and a debug target processor B running in any privilege level, the debugging feature allows A to halt B and promote B to any privilege level. As a debug host, A has full control of B even if B owns a higher privilege level than A. Accordingly, A can read/write any EL3 memory/register via B. Also, with this memory access, A can execute arbitrary code in EL3.

Raspberry Pi 3 B+ and 4 B devices through 2021-08-09, in certain specific use cases in which the device supplies power to audio-output equipment, allow remote attackers to recover speech signals from an LED on the device, via a telescope and an electro-optical sensor, aka a "Glowworm" attack. We assume that the Raspberry Pi supplies power to some speakers. The power indicator LED of the Raspberry Pi is connected directly to the power line, as a result, the intensity of a device's power indicator LED is correlative to the power consumption. The sound played by the speakers affects the Raspberry Pi's power consumption and as a result is also correlative to the light intensity of the LED. By analyzing measurements obtained from an electro-optical sensor directed at the power indicator LED of the Raspberry Pi, we can recover the sound played by the speakers.