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FOSDEM and the dangerous IPv6-only network (or how to lose the trust of newcomers)

Last year I posted about FOSDEM and the IPv6-only network as a technical solution with no problem: nobody should be running IPv6-only consumer networks, because there is zero advantage to them and lots of disadvantages. This year, despite me being in California and missing FOSDEM, their IPv6-only experiment expanded into a full blown security incident (, and I heard about it over Twitter and Facebook.

I have criticized this entrenched decision of providing a default IPv6-only network, and last night (at the time of writing) I ended up on a full-blown Twitter rage against IPv6 in general. The FOSDEM twitter handler stepped in defending their choice, possibly not even reading correctly my article or understanding that the same @flameeyes they have been replying to is the same owner of, but that’s possibly beside the point:

Let me try to be clear: I do know that the dual-stack network is available. Last year it was FOSDEM-legacy, and this year is FOSDEM-ancient. How many people do you expect to connect to a network that is called ancient? Would you really expect that the ancient network is the only one running the dual-stack routing, rather than, say, a compatibility mode 2.4GHz 802.11b? Let’s get back to that later.

What did actually happen, since the FOSDEM page earlier doesn’t make it too clear: somebody decided that FOSDEM is just as good a place as BlackHat, DEFCON or Chaos Computer Congress to run a malicious hotspot on. So they decided to run a network called “FOSDEM FreeWifi by Google”, with a captive portal asking for your Google account address and password. It was clearly a a low-passion effort, as I noticed from the screenshots over twitter, and by what an unnamed source told me:

  • the login screen looked almost original, but asked for both username and password on the same form, Google never does that;
  • the page was obviously insecure;
  • the page was served over network.

But while these are clearly signs of phishing for a tech user, and would report “Non Secure” on modern Chrome and Firefox, that does not mean they wouldn’t get a non-expert user. Of course the obvious answer of what I will from now on refer to as geek supremacists is that it’s their own fault if they get owned. Which is effectively what FOSDEM said above, paraphrasing: we know nothing of what happened on that network, go and follow Google’s tips on Gmail security.

Well, let me at least point out to go and grab yourself a FIDO key because it would save your skin in cases like that.

But here is a possible way this can fall short of a nice conference experience: there’s a new person interested in Free Software, who has started using Linux or some other FLOSS software and decided to come to what is ostensibly the biggest FLOSS conference in Europe, and probably still the biggest free (as in gratis) open source conference in the world. They are new to this, new to tech, rather than just Linux, and “OpSec” is an unknown term to them.

They arrive at FOSDEM and they try to connect to the default network with their device, which connects and can browse the Internet, but for some reason half the apps don’t work. They ignored the “ancient” network, because their device is clearly not ancient – whether they missed the communication about what it was, or it used the term dual-stack that they had no understanding of – but they see this Google network, let’s do that, even though it requires login… and now someone has their password.

Now the person or people who have their password may be ethical, and contact HIBP to provide a dump of usernames involved and notify them that their passwords were exposed, but probably they won’t. With hope, they won’t use those passwords for anything nefarious either, but at the same time, there is no guarantee that the FreeWifi people are the only ones having a copy of those passwords, because the first unethical person who noticed this phishing going on would have started a WiFi capture to get the clear-text usernames and passwords, with the certainty that if they would use these, the FreeWifi operators would be the ones taking them blame, oops.

Did I say that all the FOSDEM networks are unencrypted? At least 33c3 tried providing an anonymous 802.1x protected/encrypted connection. But of course for the geek supremacists, it’s your fault if you use anything unencrypted and not use a VPN when connecting to public networks. Go and pay the price of not being a geek!

So let’s go back to our new enthusiastic person. If something does happen to the account, it get compromised, or whatever else, the reaction the operators are expecting is probably one of awe: “Oh! They owned me good! I should learn how not to fall for this again!” — except it is quite more likely that the reaction is going to be of distrust “What jerks! Why did I even go there? No kidding nobody uses Linux.” And now we would have alienated one more person that could have become an open source contributor.

Now I have no doubt that FOSDEM organizers didn’t intend for this malicious network to be set up. But at the same time, they allowed it to happen by being too full of themselves, that by making it difficult to users to use the network, they lead to improvement in apps that would otherwise not support IPv6. That’s what they said on twitter: “we are trying to annoy people”. Great, bug fixes via annoyance I’m sure they work great, in a world of network services, that are not in control of the people using them, even for open source projects! And it sure worked great with the Android bug that, fixed almost a year before, kept receiving “me too” and “why don’t you fix this right now?” because most vendors have not released a new version in time for the following FOSDEM (and now an extra year later, many have not moved on from Android 5 either).

Oh and by the way, the reason why it’s called “ancient” is also to annoy people and force them to re-connect to the non-default network. Because calling it FOSDEM-legacy2017 would have been too friendly and would make less of a statement than “ancient”: look at you, you peasant using an ancient network instead of being the coolest geek on the planet and relying on IPv6!

So yes, if something malicious were to happen, I would blame the FOSDEM organizers for allowing that to happen, and for not even providing a “mea culpa” and admitting that maybe they are stressing this point a bit too much.

To close it off, since I do not want to spend too much time on this post on the technical analysis of IPv6 (I did that last year), I would leave you to Todd Underwood’s words and yes, that is an 11 years old post, which I find still relevant. I’m not quite on the same page as Todd, given how I try hard to use IPv6 and use it for backend servers, but his point, if hyperbolic, should be taken into consideration.

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