Website gets blocked by webfilterproxyd even without website restriction
In case someone else stumbles on this as I did...

Deleting webcontentfilter.kext is actually deleting part of Parental Controls. kext is short for kernel extension. It is better to turn Parental Controls off than to wreck it.

What was probably going on is that you need to, in the main firewall (under Security, in System Preferences), allow incoming connections from that IP address. You may need to configure the firewall manually, if so, consult a complete tutorial.

Also, 49757 is not the port the request was coming from, it is the local port the request is attempting to connect to.