A new firmware update for Trezor One devices, containing, among other improvements, a security update, expanding the application of the update released in firmware 1.6.1. The security patch fixes the same physical attack vector as the one described the aforementioned update. There is no evidence that this vulnerability has been used in practice.
Trezor Wallet interface will offer the firmware update for your Trezor One. Please make sure you have the correct recovery seed nearby before starting the update process.
Firmware Update 1.6.3 https://blog.trezor.io/trezor-one-firmware-update-1-6-3-73894c0506d