alt Hacker NewsAs far as I can tell, all of these attacks require the attacker to already be associated to a victim's network. Most of these attacks seem similar to ones expected on shared wifi (airports, cafes) that have been known about for a while. The novel attacks seem to exploit weaknesses in particular router implementations that didn't actually segregate traffic between guest and normal networks.
I'm curious if I missed something because that doesn't sound like it allows the worst kind of attacks, e.g. drive-by with no ability to associate to APs without cracking keys.
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I'm a co-author on the paper: I would personally indeed not use the phrase "we can break Wi-Fi encryption", because that might be misinterpreated that we can break any Wi-Fi network.
What we can do is that, when an adversary is connected to a co-located open network, or is a malicious insider, they can attack other clients. More technically, that we can bypass client isolation. We encountered one interesting case where the open Wi-Fi network of a university enabled us to intercept all traffic of co-located networks, including the private Enterprise SSID.
In this sense, the work doesn't break encryption. We bypass encryption.
If you don't rely on client/network isolation, you are safe. More importantly, if you have a router broadcasting a single SSID that only you use, we can't break it.
What about XFinity, which by default shares the wifi you pay for with strangers to create access points around the city?
Access points frequently have multiple BSSIDs even if just for broadcasting on 2.4 and 5 at the same time. Any multiple AP scenario will have them regardless. Couple that with weak duplicate MAC checking and shared GTK (WPA2-PSK) and the attack becomes trivial. I imagine old hardware will be broken forever. Especially pre 802.11w.
That's my read as well. It's bad for places that rely on client isolation, but not really for the general case. I feel like this also overstates the "stealing authentication cookies": most people's cookies will be protected by TLS rather than physical layer protection.
Still an interesting attack though.
That’s my read as well. It’s not good, but it’s not nearly as bad as the headline makes it sound.
The attacker doesn't need to be connected to the victim's network, only to the same hardware, the hardware's loss of isolation is the unexpected problem.
Their University example is pertinent. The victim is an Eduroam user, and the attacker never has any Eduroam credentials, but the same WiFi hardware is serving both eduroam and the local guest provision which will be pretty bare bones, so the attacker uses the means described to start getting packets meant for that Eduroam user.
If you only have a single appropriately authenticated WiFi network then the loss of isolation doesn't matter, in the same way that a Sandbox escape in your web browser doesn't matter if you only visit a single trusted web site...