@dc42 thanks!

I have a Vormvrij Lutum ceramic 3d printer in my studio that uses a Duet 2 Wifi board running Firmware 3.2.2. When I connect my Mac to the Duet Wifi Hotspot I start seeing a flood of 'Possible virus attack' errors in console of the web interface and on the 3D printer build in touchscreen. All the errors seem to be related to ocsp traffic from my Mac.

I found these two topics referencing the same issue but there it is mentioned that this issue should have been solved in firmware v3.1.1?:
Virus warning message?
DuetWifi-error: filename too long

I tried blocking traffic to ocsp servers using Little Snitch and also all outgoing connections from the trust & ocspd processes which seem to generate that traffic but did not solve anything.
I'm also not running any AV software.

What else can I try?