I actually thought I was done with the pre-con portion of my Hacker Summer Camp blog post series, but it turns out that people wanted to know more about “the most dangerous network in the world”. Specifically, I got questions about how to protect yourself in this hostile environment, like whether people should bring a burner device, how to avoid getting hacked, what to do after the con, etc.
So, is it “the most dangerous network in the world”? Well, there’s probably some truth to that in the sense that in terms of density of threats, it’s likely fairly high. In terms of sheer volume of threats, the open internet is obviously going to be a leader.
First off, the DEF CON network is really multiple networks. There’s the open WiFi, which is undeniably the Wild West of computers, and there’s the DEF CON “secure” network, which uses WPA2-Enterprise (802.1x) with certificates to verify the APs. The secure network also features client isolation. Additionally, the secure network is monitored by a dedicated NOC/SOC with some very talented and hard-working individuals. I would assert that being compromised on the secure network is approximately the same risk as being compromised on any internet connection.
So, there’s 0-day flying around left and right? Not so much. Most of the malicious traffic is likely coming from someone who just learned how to use Metasploit or just found out about some cool tool in a talk or workshop. Consequently, it’s unlikely to have much impact for those who patch and are security-aware.
What you will see a ton of is WiFi pineapples. People will go buy one at the Hak5 booth, and then immediately turn it on and try to mess with other attendees. It gets pretty old, pretty quickly. Just make sure you’re connected to the DEF CON Secure WiFi and this will be a minimal problem (maybe a denial of service).
In all honesty, the con hotel WiFi is a worse place to be than DEF CON secure, by a large margin. Plenty of stupid things happening there.
The minimalist carries a flip phone with a burner SIM. He/she maintains contact with friends using SMS or (gasp) actual phone calls. No laptop, no smart phone to be compromised. This is a great approach if you’re not going to participate in any activities that require tech on hand. If you’re going to hang out, listen to a few talks, and drink, this is the approach with no need to worry about getting compromised.
No, this isn’t about Burning Man, although DEF CON is kinda like Burning Man for “400-lb hackers in basements”. This hacker brings a burner version of everything: so a smart phone, but a cheap burner. This probably will get compromised, as their carrier hasn’t pushed a patch in 3 years. (And even before that, it shipped with some shady pre-installed apps that send all your contacts over plaintext to a server in China…). They also bring a $200 Dell or HP laptop with Kali Linux on board.
They connect to the first WiFi they see, never mind that it’s labeled “FBI Surveillance Van 404”. If you plan for your hardware to get pwned, it doesn’t really matter if it’s bad WiFi, right?
Of course, in order for this to work correctly, you have to never use your devices for anything sensitive. Hopefully the urge to check your real email doesn’t get too strong. Or maybe your card is suspended for potentially fraudulent activity (like that $300 SDR) and you decide to log in “briefly” to reactivate it. This route really only works if you can maintain good OpSec.
“Good Enough” Security
If you can set aside ego and assume nobody is willing to try using a $100k+ O-day on you, you can get by with a reasonable level of security. This involves bringing a modern fully-patched phone (iPhone or “flagship” Android phone), and optionally a well-secured laptop.
For the laptop, I’ve previously discussed using a Chromebook. Even with dev mode for crouton, I believe this to be reasonably safe from remote exploitation. This can also be cheap enough to be a disposable device. In my previous post, I suggested 3 Chromebook options:
Alternatively, you can get a cheap laptop and run fully-updated Windows 10 or Linux with a firewall enabled and be in a pretty good state for passive attacks over the network.
In either case, you should then run a VPN. I like Private Internet Access, but there’s a lot of options out there, or you can even run your own OpenVPN server if you’re feeling adventurous.
There’s never a guarantee of security, but with updated devices & good security hygiene, you can survive the DEF CON networks. The basic elements involved are:
- Fully updated OS
- Be super careful
- Use a VPN
- No Services Exposed
Good luck and see you at Hacker Summer Camp!