Canon, like many manufacturers, uses a specific bootloader process for updating the internal firmware of its cameras. Because many Canon cameras lack USB mass storage control for low-level flashing, the company relies on a legacy method:
The next time you see this cryptic uupd.bin staring at you from your SD card, you will know exactly what it is: a silent messenger that once carried new life into your camera’s firmware. And now, it is ready to be archived or deleted. sd card uupd.bin
You may have started a firmware update process months ago, gotten a "battery low" warning, and aborted. The camera wrote uupd.bin to the card in preparation but never completed the flash. Or, you started the process, the camera rebooted successfully, but the file was never deleted as part of the cleanup routine. Canon, like many manufacturers, uses a specific bootloader
