When exiting sleep via CAN, the microcontroller does not show the cause for the reset. The RSSR register is empty.

[Alex_Itelma]

When exiting sleep from Standby Mode via CAN, the microcontroller does not show the cause for the reset. The RSSR register is empty. Why?

[run]

Standby mode would not reset the MCU.
Powerdown mode could reset the MCU, but there is no flag set in RSSR register.
You may check WKU->PFR for powerdown mode to determine which WKU_PINn to wake up the MCU.