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

redthreatsec.com

81–90 of 94 posts

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

#81

Part 2 article goes into a bit more of detail, but the funniest thing is that they requested access to the SNMP MIBs of the controller and never got them > I requested MIBs from Q-Free but didn’t receive any follow-up after the request and I never received access to the MIBS, so it was back to square one. Then you go look at https://www.freethemibs.org/advocates and... there they are, "advocates" for free MIB access.…

What are SNMP and MIBs?

Simple Network Management Protocol. Management Information Base.

https://en.m.wikipedia.org/wiki/Management_information_base

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

#82
post #20

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

I would hope they still use physical interlocks instead of implementing it in software, even though it’s semiconductors instead of relays controlling stoplights these days.

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

#83

Earlier quoted context omitted.

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…

> (believe it or not, in some localities a "red clearance" time - all red - is not required and lights will go from yellow in one direction to green in another.) This was definitely true in the past, I feel like the concept of a 'red clearance time' is something that only became common within the last 5-10 years. Do you think it has become (with rare exceptions) ubiquitous at this point?

I moved up to Oregon for a few years during/after the pandemic. I can say from experience that the entire state consistently did not have red clearance times at least up to when I left in late 2023.

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

#84
post #19

If you just want a green light an easier way to get one is to flash the infrared strobe pattern that gives fire trucks green lights. Seems simpler.

I've never seen that in the real world. In my area, the lights go RED in all directions. Much safer option.

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

#85

Earlier quoted context omitted.

I am aware of a municipality local to me that, as part of a franchise agreement for a new ISP entering the community, had the ISP run fiber to every traffic cabinet. They're connected back to the city network in a VLAN that's "behind the firewall". >sigh<

Because of course a controller for a traffic light needs gigabit fiber internet connectivity....

The issue is that legacy copper plant has a finite lifetime. Paper insulated lines are already mostly useless today. If you have to replace infrastructure you may as well select a more robust modern alternative.

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

#86
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…

> 90 days isn't really an industry standard. It's what Google unilaterally decided upon when they chose to staff up Project Zero

Every published vulnerability disclosure policy I've found in a quick look around has a 90 or 120 day timer involved somewhere. There may be some variation in exact details but there's not significant disagreement in the industry aside from those who don't want any firm time limits at all.

Also to be specific Google's policy is actually 90+30, you have 90 days to release a patch and as long as you do that details will be withheld an additional 30 days from the release of the patch. There is also an option for a 14 day grace period on the patch release if a vendor has been working in good faith and Google has reason to believe they will actually get it done in that time.

> 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,

If you are competent software developers in 2024 you have fully automated test processes and if your things are expected to be connected to the internet you should have the ability to remotely update them. These are not things that anyone has any excuse to not understand. I am well aware that OT equipment vendors are often absolute horror shows from a software development standpoint, that's not an excuse for anything. If they can't do things right they deserve everything that happens to them and their customers should hold them accountable for the inevitable result.

> which in turn implies that users aren't involved in the decision about whether to upgrade or not. It also assumes you can do this as often as you want. This is a strong set of assumptions that happens to be true for Google but isn't true of SCADA shops.

It's an assumption that has to be true of anything connected to the open internet. If a bad actor discovers the exploit and starts using it against exposed systems you won't have a choice but to patch it yesterday, at which point a 90+30 deadline will feel like all the time in the world.

The simple answer of course is if for whatever reason you can not patch the thing in such a timeframe it should never be connected to the internet and connections between internet-connected systems and the private network should be severely restricted and heavily monitored for unusual activity.

At that point you don't care about whether exploit details are public because you know every single person who could potentially implement it.

> Given the unclear threat model here (how does one get access to the networks that these are attached to?

The article also mentions this, but you answer your own question a paragraph later.

> In many cases these devices will be reachable from the public internet, and in some of those cases it will be intentional.

And again the fact is if it is on the internet it must be rapidly patchable. If short-notice patching is not viable for your use case then don't put it on the internet. Very simple, no exceptions.

> But is the security bug there on the controller or in the network setup that allows that access?

Yes. If the intentional access controls can be bypassed that's a bug in the controller, but if the OT device is accessible to the general internet in the first place that's a bug in the network setup.

> It's probably easier to properly firewall off the controllers than continuously patch all the controller firmwares themselves, especially as the latter done wrong could easily enable hackers to perform a worse-than-Crowdstrike level takedown of all controllers simultaneously.

Also yes.

> It's really not clear that the model that works well for web browsers will ever work well for infrastructure.

The model is "if it is exposed to the internet and there is a remotely exploitable vulnerability known it must be either patched or not exposed to the internet anymore". It doesn't matter what the thing is, be it browsers, infrastructure, medical, etc. Either take it off the internet or be ready and willing to patch it on short notice.

> We just saw an awesome demo of what can go wrong when rapidly hot-patching security updates into critical infrastructure computers goes wrong.

I'd argue that was more of a demo of what will go wrong when you don't have automated testing and why you should always have staged deployment when doing things at scale.

That said, I'll return to the same point, how much infrastructure that wasn't connected to the internet was affected? Every system that was affected was allowed to download software from the internet controlled by a third party.

This discussion reminds me of the recent discussion around Entrust where a lot of the excuses were around certs being used in places where they could not be easily rotated, which led to the obvious question of "what would these users have done in the event of a key compromise?" having no good answers. When you're using internet infrastructure you need to be able to move quickly from time to time.

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

#87
post #20

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

No. There is a thing called a "conflict monitor." It uses a hard wired control board. This board has solderable links on it. When you connect a link you're describing two phases which CANNOT be green at the same time. You then slide the board into the monitor.

If the monitor sees that current for the green lights on two opposing phases are green at the same time, or any of several other fault conditions, it will trip, then "throw the intersection into flash" as a roadway protection mechanism. At this point none of the controllers or other logic is capable of controlling the intersection and it stays in flash until someone comes and manually resets it.

Here's an example of what one of those cards looks like. Wonderfully old school and absolutely nothing active about it.

https://i.ebayimg.com/images/g/9roAAOSwKOFfh3gM/s-l1600.jpg

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

#88
post #18

Sounds like the company realised they can't solve the issue in 90 days. Betting a combination of infrastructure scale problems, terrible tech, no-longer-building old solutions, no maintenance fee's built in and contractors who hate them. So they pulled the only lever they had left, which was the lawyers. Same time, RedThreat's email was kinda (maybe rightly) hostile. Read from the other side it's basically "You have…

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…

I work in accessibility as an engineer.

Now that digital web properties are included the ADA, there are law firms out there essentially doing the same thing. They are actively scanning the internet to find companies who have accessibility issues which are primarily widgets or overlays. Then they're emailing them the issues and "allowing" them 90 days to correct the issues, otherwise, they will be sued.

There's been like a 400% increase in these suits over the last two years because you can go after a large company and even if they fix one issue, you can find another issue and sue or threaten them on that one as well.

My co-workers think its great because of the pressure to solve these issues that really do need to be fixed. But like in this instance, its a fine line between doing something positive and extorting money for yourself or in our case, a law firm.

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

#89

Earlier quoted context omitted.

I am aware of a municipality local to me that, as part of a franchise agreement for a new ISP entering the community, had the ISP run fiber to every traffic cabinet. They're connected back to the city network in a VLAN that's "behind the firewall". >sigh<

Because of course a controller for a traffic light needs gigabit fiber internet connectivity....

Cameras are cheap these days, and with a decent fiber link, just install one for each crossing, feed the live streams back to the pig sty and whoops you suddenly have all you need for a comprehensive monitoring solution to track people. No matter if they're suspects or not.

The shit you saw on NCIS a decade ago and dismissed as "science fiction" is getting ever more to reality.

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

#90
post #20

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

I remember back in the day some guy was selling the strobe light devices that emergency vehicles use on some nefarious site and it came with a warning that its a felony to even possess one of these and you should only use it for "research" purposes wink wink.

The funny part of his ad was him saying its still dangerous AF to just switch a light to green so quickly, it has the very real potential to cause accidents which back in the early aughts when this was online, I could totally believe him.

You don't need a light to change to green in all directions, using this and then thinking you're good to go and you blow through the intersection while someone is trying to beat a yellow light in the opposite direction could be disastrous.

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