On Trezor One devices before 1.8.2, a side channel for the row-based OLED display was…

Summary

On Trezor One devices before 1.8.2, a side channel for the row-based OLED display was found. The power consumption of each row-based display cycle depends on the number of illuminated pixels, allowing a partial recovery of display contents. For example, a hardware implant in the USB cable might be able to leverage this behavior to recover confidential secrets such as the PIN and BIP39 mnemonic. In other words, the side channel is relevant only if the attacker has enough control over the device's USB connection to make power-consumption measurements at a time when secret data is displayed. The side channel is not relevant in other circumstances, such as a stolen device that is not currently displaying secret data. NOTE: this CVE applies exclusively to the Trezor One, and does not refer to any issues with OLED displays on other devices.