The first and main thing is to ensure that the firewall on your host is configured to properly drop incoming packets with source or destination address set to 127.0.0.1.
Under normal circumstances, there should be no packet coming from the network and showing such addresses. However an attacker may attempt to forge such packets in order to reach your local listening services.
I do not know which kind of other services are listening on your machine, but if any service can be used as a relay you must ensure it is properly configured to prevent to relay anything to the local listening services.
For instance, if you have an HTTP proxy running on this host, an attacker can use this proxy to request the host "127.0.0.1": from the firewall perspective this will be a legit connection coming from the network to the proxy service, and locally this will be a legit communication between two local services (the proxy and the targeted local port). The HTTP proxy here is just an example, such technique may also work with other services, including services where relaying connections is not the main functionality (the FTP bounce attack for instance is a classical example of such threat).