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Comment by dataflow | Hacker News Reader

For the life of me I don't understand either of these:

- Why, after so many darn versions of Wi-Fi security standards, we still have attacks that just bypass encryption entirely. How do these not get caught during the design/implementation with so many people studying the specs for decades?

- Why 99% of end-users should even care about these issues from a security standpoint, given they already have https and such (because the transport is already assumed to be untrusted), and given that people have been connecting to "unsecured" networks for decades now, without the sky falling. Is the added security of each version of WPA even relevant to normal people?

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> How do these not get caught with so many people studying the specs for decades?

Because extremely few people actually look at the detailed specs. You’d think more people did, but it turns out they don’t.

> Is the added security of each version of WPA even relevant to normal people?

It’s relevant for those who misguidedly have their network infrastructure set to trust all local network connections. In my experience, many people do.

> Because extremely few people actually look at the detailed specs. You’d think more people did, but it turns out they don’t.

Well that's depressing :(

> It’s relevant for those who misguidedly have their network infrastructure set to trust all local network connections. In my experience, many people do.

For 99% of people worrying about "network infrastructure" would only be relevant at home, right? So the threat model here is some nefarious nearby actor (your tech-savvy neighbor? someone else parked nearby who hates you and knows how to do these hacks?) is trying to hack you? How often does this actually happen?

I'd argue the number of startups that have trust all local network connections is not far behind. I doubt a company seriously considers their wifi connectivity as a threat vector until they get to a series B size.

Hypothetically I'd imagine if you take early startup infrastructure snooping + <insert criminal act here> you probably have a criminal enterprise that's cashflow positive.

Startups, sure, but <1% of people are running such startups I imagine. So it's fair to say this isn't relevant to most people?

Many elaborate scams are not relevant to most people, but only to people with money. Most phishing attacks are not relevant to most people, only to people in some important enough positions, or with access to interesting enough networks.

But the damage of such attacks is still large enough to care.

I'm sure there are quite a lot of non-tech-startup small businesses in the same boat. And sure, still less than 50% of people own such business, but that something doesn't directly affect a majority doesn't mean it's not important.

I guess, to clarify, what I'm trying to get at is, should someone who hears "this computer/router/whatever supports WPA{N+1}, whereas that one just supports WPA{N}" factor that into their purchasing decision or not. And the answer I see seems to be, "if this is just for your household use, then no, unless you have reason to believe someone in your proximity would try to hack you".

Users certainly do still need to care about having encryption at the physical layer. Wi-Fi networks having done key exchange and taking that out of the equation for regular users so that they get some guarantees of encryption without constantly doing key exchange on their own is a big deal.

You are correct that transport layer security like HTTPS can protect many connections end to end, however if you have MITM attacks on your physical layer they can do certificate pinning attacks, redirection attacks and more.

Sure, there is a good chance they won't get into your Gmail because Google embeds the certificates of their and the top other websites into their browser, but that's not much consolation.

Regarding your first point, the flaws are almost always in the implementation, not the design, though specs inevitably leave too much to the implementation.

Regarding your second point, security works in layers. Much like it's better to have two locks than one.

I also struggle to understand this. If I'm on a VPN or only using HTTPS, is my data safe?

Yes

Technically I think it depends on whether someone can mess with your connection enough to convince the browser to fall back to HTTP. And whether you could be tricked into entering credentials on the wrong page.

How does your VPN handle having its connections blocked by an adversary in the middle?

Does it “fail open”? Or silently fail? Does it alert the user?

Does anything on your device use non-TLS? Software updaters? Are they susceptible to downgrade/fallback attacks?

When I last properly explored this I found a good number of automatic software updaters would fall back to plaintext HTTP (or just didn’t use TLS) and often didn’t perform much or any signature checking on updates.

So the way it works is that if you have a setup like so: Your client <-- bad actor --> Public Webserver.

Your first layer of defense is assuming its hard for a bad actor to get to that spot (which this attack is showing is possible).

Now the next thing the bad actor needs to do to compromise your traffic is deal with HTTPS/VPN. The only real way to do that would have to be to convince your client that the certificate from the CA that's signing the https traffic received from the webserver/VPN provider is trusted/ (i.e a classic MITM with a compromised client and a local CA).

Most clients will warn you that this cert is unrecognized, so with an untampered client unless you just clickthrough the cert warnings you will be protected. However, people often ignore cert warnings and that means that all your traffic is now cleartext for the bad actor.

Your data is safe, but you can be prevented from connecting at all.

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