Last year I had a big dispute with my ISP that was refusing to support or provide proper WiFi on their router, even while they touted a trademarked brand-name to do it. I ended up turning their router into Bridge Mode and purchasing a real router that could do WiFi. I did this extremely reluctantly, because every other personally-owned router had contracted malware.

After installing the new router (Netgear) my HP LaserJet began printing error pages. Like, I had done nothing to send anything to it, but a blank error page or three would pop out of it at very random times.

It took awhile to narrow down and diagnose this. But it turned out that the Netgear system had a very... proactive network malware detection system. It was red-team scanning my LAN for "vulnerabilities" or exploits or the presence of malware (I think just known vulns). It was a known side-effect of these scans, where it would tickle an RTSP TCP port of some kind and the HP printer would respond with its error printout.

I was so livid that the router was scanning the LAN, basically unbidden and completely undocumented. Even worse, they were not sharing the logs or results of that scan with the consumer. No, they were being sent back to the Netgear mothership, and their cybersecurity vendor overlords. So the scans were not designed to benefit me; they were simply designed to spy on everyone from a privileged vantage point. Now I ask you, why is a piece of kit that is supposed to be "yours" compiling secrets about your network, hiding them from you, and turning them over to, I guess a big database for hackers to leak in due time? This is not a question of "well, devices hooked up to a network should not be vulnerable" if the devices were contained in a private network, and 100% inaccessible from outside, and only attackers inside my perimeter could do these exploits in the first place.

Thankfully I found a way to disable this. Their "security" shitware is still spamming DNS and I may be forced to disable that as well. Meanwhile, routers 100% cannot self-introspect or self-diagnose and find their own malware. I've said it once; I'll say it again: consumer routers are the Achilles Heel to your network. They are ideal points of compromise for any actor to gain a foothold and pivot, or simply gain persistence undetected. Your ISP doesn't care, and your vendors don't care. Perhaps you should.