I encountered the same problem, I received ST-LINK V3SET three days ago, and is a new unit but cannot do a firmware upgrade via STM32CubeProgrammer as picture shown below:
I have the same problem in a linux machine. I used the en.stsw-link007_v3-10-3 utility to update the st-link firmware of a STM32H747I-DISC0 module and it worked ok. Next, with the same USB cable and software utility the upgrading process failed for a second STM32H747I-DISC0 module and this module is now bricked.