Due to security reasons, I need an USB that has the switch to set it physically read only, because in this way I can be 100 % sure that it can't get infected when I connect it to an infected device. I can not find any good and trusted brand that sell USB with that switch in my country, so people suggested me to use and SD card that has that switch. I found some good SD cards with that switch, but sadly I need a SD card reader to connect it to USB ports (something like this https://amzn.eu/d/ewl1uU9).
So I'm wondering: If I turn on the read only switch of the SD card, I put the SD card in the SD card reader and I connect the SD card reader to an infected PC, could a virus still infect the SD card reader firmware? If the answer is yes (I afraid it is), are there any other solutions to connect a USB or something similar to a PC and be physically protected?
Yes, I'm pretty paranoid, but I was used to use DVD to do that stuff, but now with 4 or 8 GB you can't do much, and some PC manufacturers are sadly removing DVD players