Hi,
I tried to reproduce the issue:
- installed a local apache2
- configured the server to use a self-signed certificate
- created a strLoader to send POST request to this webserver
- used modsecurity to dump the payload of the POST request
As you can see on my screenshot, the POST request to my SSL enabled webserver is processed as expected.
Did I get your problem right? What exact error message do you get? What is the exact reason, because you used the CORS proxy?