Many computer users don't realize it, but for most people their internet router is the most important electronic device in their home. It links most of their other devices together and to the world, so it has a highly privileged position that hackers can exploit.
Unfortunately many consumer and small-business routers come with insecure default configurations, have undocumented backdoor accounts, expose legacy services and have firmware that is riddled with basic flaws. Some of these problems can't be fixed by users, but there are many actions that can be taken to at least protect these devices from large-scale, automated attacks.
Don't let your router be a low-hanging fruit for hackers.