Firewall pinhole (original) (raw)

In computer networking, a firewall pinhole is a port that is not protected by a firewall to allow a particular application to gain access to a service on a host in the network protected by the firewall. Leaving ports open in firewall configurations exposes the protected system to potentially malicious abuse. A fully closed firewall prevents applications from accessing services on the other side of the firewall. For protection, the mechanism for opening a pinhole in the firewall should implement user validation and authorization.