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Give Me the Green Light Part 1: Hacking Traffic Control Systems

redthreatsec.com

91–94 of 94 posts

Re: Give Me the Green Light Part 1: Hacking Traffic Control Systems

#91
post #18

Earlier quoted context omitted.

The 90 day window is an industry standard for zero-days, how the author worded it is neither here nor there. 90 days is ample time for even a half-functioning organization to address the issue in some way. I agree with Red Threat’s decision to not show their hand in the first email. The altruistic take on this is that they do not want the email to fall upon deaf ears (or even a bad actor within a company) and would p…

90 days isn't really an industry standard. It's what Google unilaterally decided upon when they chose to staff up Project Zero and reflects their assumptions being, as they are, a company that grew up on the web. One of those assumptions is that you have fully automated test processes and the ability to remotely update any/all installs of your software within a week or so, which in turn implies that users aren't invo…

> could you just hotwire the lights themselves and bypass the controller?

Assume you're a bank robber... place a bug (e.g. a raspi with an lte dongle) in a cabinet somewhere, now you control all traffic lights in the city. Then when you do the heist, progressively turn each intersection you pass all-sides green, and dumbass drivers will do the rest and prevent the police from catching up with you.

At least here in Germany, IIRC there used to be a mandate for a "detect conflicting greens" hardware interlock - pretty simple, wire the green light powers to AND gates, and if they trigger, shut down the cabinet hard. Same for a red light burning out - measure the current on each red light power line, if it drops below a threshold, shut down everything else to avoid a driver not seeing any light and t-boning someone who legitimately has green.

But a system without such a hardware interlock will just happily do what is asked of it.

Re: Give Me the Green Light Part 1: Hacking Traffic Control Systems

#92

Earlier quoted context omitted.

> for any traffic controller you happen to find on a network But how would one get on such "a network" in the first place? I assume it would involve physically opening a (hopefully locked) cabinet in public near the road? So just a bit of cutting/picking reveals an ethernet port, you drop in a wireless bridge, close it back up, and then hack from a parked car?

Well, the "locked" cabinet generally uses the same key everywhere in North America, which isn't a great start :) A number of agencies put these controllers directly on the Internet (a search on Shodan for some telltale strings produces concerning numbers of hits). Others will use one giant flat network across their entire city - so if you get access at once location, you have access to the entire network. This could…

Every “genie” lift has the same key Most “skyjacks” have the same key, there are maybe 3 iterations. Tractors have a lot of similar if not the same keys RV handle locks (not padlocks) have about 8 different combinations - they are color coded. Eg your RV has the purple or green key. Dead bolts are unique Every single RV storage lock is the same, if you have an RV look at the storage lock and if it says “ CH751 “ , well now you know :)

Re: Give Me the Green Light Part 1: Hacking Traffic Control Systems

#93
post #20

Can you turn all the lights at a given intersection green at the same time?

Generally no, this is something from fiction. I'm mostly familiar with North American traffic signal control, and in those traffic cabinets there is a device known as an "MMU" (Malfuction Management Unit) which acts as a safety monitor for the rest of the traffic cabinet. That device will catch so-called "conflicts" (two conflicting directions green at the same time) and put the intersection into a fail-safe state (u…

Fiction... indeed, science fiction. There was a short story (I believe in Analog) in the 1960s about this, later amplified by the author into a book.

But getting to your real point, about the use of an MMU safety monitor: I'm sure this works. But I confess, the first thing I thought about when I read that was Cloudstrike's explanation of their pre-release testing mechanism: running "validation checks" on the content, rather than running the actual software. Had they actually run their release, they would surely have detected the bug, since it apparently bricked every single Windows machine that downloaded it.

Re: Give Me the Green Light Part 1: Hacking Traffic Control Systems

#94
post #26

Earlier quoted context omitted.

How about switching lights in quick succession, enough to cause real-world issue, but avoiding the direct conflict?

Now you start to get into the differences between the various standards :) In NEMA TS2 (and the more modern ITE ATC), the MMU does enforce a yellow clearance time - you need the light to turn yellow for a period of time before a conflicting phase goes green. Usually this is a few seconds. Changing phases rapidly would likely confuse drivers, but in _theory_ shouldn't cause a collision if people respect yellows. (beli…

"...if people respect yellows." Of course they respect yellows! Yellow means "go faster so you can make it through the intersection."
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