[bigChris]

Rsync worst issue is someone port scanning and brute force their way into your system. Turn off your port.

[seunosewa]

Most people use rsync over ssh

[hatware]

Don't most consumer routers have all ports blocked? Who is connecting a computer directly to the modem these days?

[stavros]

Most of them do NAT, which isn't semantically the same as blocking all ports, but functionally it is.