said by Bill_MI:
I'll do some speculation just to see how close I am...
Many of you may have noticed when you try to access your own public IP you get the router web page. Still true? My speculation is that this rule is made advantage of. It's not your LAN IP it's a public IP (that happens to be your own) so it'll get by a lot of security fixes against local addressing. Cross-Site Scripting (XSS) had exploits to access local LAN addresses but this Linksys quirk is sort of an invitation.
IF that's all it is... securing your password off default would be #1. But everyone here should already know THAT, anyway.
Of course, if the Linksys router(s) in question have a default backdoor password, that might not help. My Netgear WNR1000v2-VC (running stock Netgear firmware) has such a hidden "root" password, and I take advantage of it when I occasionally need to look at something that the html admin pages don't show me by running a Netgear utility called "TelnetEnable". That utility does exactly what the POC seems to be doing, it opens up a Linux command line interface (with "root" privileges) to the router (and the "admin" password I have setup is irrelevant to this process).--
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