One Step Forward, Two Steps Back

Were I asked I would summarize the Internet of Things as taking one step forward and two steps back. While integrating computers into everyday objects offers some potential the way manufacturers are going about it is all wrong.

Consider the standard light switch. A light switch usually has two states. One state, which closes the circuit, turns the lights on while the other state, which opens the circuit, turns the lights off. It’s simple enough but has some notable limitations. First, it cannot be controlled remotely. Having a remotely controlled light switch would be useful, especially if you’re away from home and want to make it appear as though somebody is there to discourage burglars. It would also be nice to verify if you turned all your lights off when you left to reduce the electric bill. Of course remotely operated switches also introduce the potential for remotely accessible vulnerabilities.

What happens when you take the worst aspects of connected light switches, namely vulnerabilities, and don’t even offer the positives? This:

Garrett, who’s also a member of the Free Software Foundation board of directors, was in London last week attending a conference, and found that his hotel room has Android tablets instead of light switches.

“One was embedded in the wall, but the two next to the bed had convenient looking ethernet cables plugged into the wall,” he noted. So, he got ahold of a couple of ethernet adapters, set up a transparent bridge, and put his laptop between the tablet and the wall.

He discovered that the traffic to and from the tablet is going through the Modbus serial communications protocol over TCP.

“Modbus is a pretty trivial protocol, and notably has no authentication whatsoever,” he noted. “Tcpdump showed that traffic was being sent to, and pymodbus let me start controlling my lights, turning the TV on and off and even making my curtains open and close.”

He then noticed that the last three digits of the IP address he was communicating with were those of his room, and successfully tested his theory:

“It’s basically as bad as it could be – once I’d figured out the gateway, I could access the control systems on every floor and query other rooms to figure out whether the lights were on or not, which strongly implies that I could control them as well.”

As far as I can tell the only reason the hotel swapped out mechanical light switches with Android tablets was to attempt to look impressive. What they ended up with was a setup that may look impressive to the layman but is every trolls dream come true.

I can’t wait to read a story about a 14 year-old turning off the lights to every room in a hotel.

One thought on “One Step Forward, Two Steps Back”

  1. I can’t wait to stay at a hotel where my lights, TV, and curtains can all be manipulated by someone outside my room. Hey, what about the thermostat? We should include that as well.

    This is not quite as bad as someone hacking a car while it’s being driven on the freeway, but it’s definitely some steps backward.

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