A group of vulnerabilities in networks are those that come from the network device themselves. These vulnerabilities are normally a result of manufacturer error and, once discovered by attackers, can be exploited in any organization that uses the affected network devices. Before these devices can be patched by the manufacturer, data remains exposed to attackers. Taking them offline could prove to be difficult, especially in large organizations that can't afford downtime. Therefore, it isn't surprising to find that some vulnerable network devices are still in use, despite this known by network admins. It's estimated that 73% of all organizations are using vulnerable networking devices.
Here's a snippet from an article on vulnerable network devices:
