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Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

arstechnica.com

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Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#31

Post by zamadatix »

gipsies wrote: post #21
zamadatix wrote: post #4

Downgrade attacks: WPA3 has a transitional mode which allows legacy WPA2 clients to connect. In this mode legacy WPA2 security issues are still present. Is this really a discovery or a given? How is WPA3 supposed to protect against it without requiring either WPA2 clients to be upgraded to support WPA3 security fixes (in which case you don't need WPA2 support anymore anyways) or without dropping support for transitio…

If we look at the paper then these remarks are all discussed: - Defending against downgrade attack: "A client should remember if a network supports WPA3-SAE. That is, after successfully connecting using SAE [..] the client must never connect to this network using a weaker handshake". The Google Pixel 3 is thankfully already doing this, but others aren't. So perfectly preventable, and something the Wi-Fi Alliance coul…

"A client should remember" just transfers things to first trust attacks, if you want to do it right you'd have to make sure you add the network to the device as WPA3 only from the get go.

Side channel attacks, sure, the standard could also have just said "don't be vulnerable to side channel attacks when generating secure data" along with everything else you should do to make a secure system.

Does it really matter how efficient the DoS attack is if any consumer gear can do the in efficient future proof version anyways? As far as intelligent attacks go isn't this yet again an implementation detail where the AP should rate limit responses to a particular client based on it's resources?

Sure, Greenfield things should be written the best they reasonably can be but not being the best something could be doesn't equate to insecure. It's a valid complaint about the standard but not an insecurity.

Again the paper had valid interesting findings in real world side channel attacks and some valid complaints that Dragonfly could have been implemented in better way but it's not focused on attacking those instead it's focused on making big noise about how bad running things in WPA2 mode is bad under the title of being about WPA3.

Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#32

Post by mschuster91 »

sandworm101 wrote: post #26
blitmap wrote: post #11

Earlier quoted context omitted.

Preface: I am not at all an expert on WiFi In WPA2 you can send deauthentication "frames" to clients to get them to disconnect from the access point. Later I was told these "control frames" can now be encrypted, with an extension/modification to WPA2 supported in the better consumer wireless routers like Linksys? In response to your Denial of Service point: Does WPA3 make it harder to disconnect clients? (or are you…

There is only so much effort one can put into denial of service attacks in wireless. The fact that this involves radio frequencies means there is always a nuclear option: massive broadcasts of white noise. There is no way for wifi devices to adapt to such an attack. So the fact that some denial attacks can happen using exploits is moot. If the attacker really wants to hold your network down he isn't going to bother w…

Yeah but if you're a sleazy hotel chain that simply wants people to use their crappy expensive wifi instead of personal hotspots then you can't use the "nuclear option" as the white noise will also fuck up your network.

This is the type of attack that is being defended against here, not white-noise bombs.

Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#33

Post by throw0101a »

zamadatix wrote: post #4

Downgrade attacks: WPA3 has a transitional mode which allows legacy WPA2 clients to connect. In this mode legacy WPA2 security issues are still present. Is this really a discovery or a given? How is WPA3 supposed to protect against it without requiring either WPA2 clients to be upgraded to support WPA3 security fixes (in which case you don't need WPA2 support anymore anyways) or without dropping support for transitio…

> Dragonfly downgrade:

When WPA3 was announced, some people here were very skeptical of the Dragonfly protocol:

* https://news.ycombinator.com/item?id=17402274

Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#34

Post by mschuster91 »

rdl wrote: post #23

My dream is to eliminate PSK from all the networks I care about/am responsible for, but it's really challenging to deploy 802.1X in anything but a fully managed enterprise (and also hard when you also have random other IOT/etc. type devices; usually the "important" ones you can just put onto wired network, and the unimportant ones go onto dedicated psk, but it's still a pain. Still hate it all less than captive porta…

> and also hard when you also have random other IOT/etc. type devices

Chromecast and Apple TV can't do 802.1x at all, same for every brand of Smart TV I've encountered. Android is a hit and miss, while Samsung and HTC support tends to be decent, cheaper phones don't have it in their test paths.

IoT devices? Gotta be lucky if you can get normal WPA2 running stable against enterprise-class APs. That's a whole new house of cards.

At work I actually had to put up a completely separate wifi network including access points and DSL uplink. Crap gear bought for testing isn't going to get access to the corp network for security reasons anyway and we had lots of issues with using an alternative virtual network on the enterprise APs as most of it seems to be tested against consumer FritzBoxes and 20€ APs, not against Cisco stuff worth hundreds of €.

Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#35

Post by xoa »

rdl wrote: post #23

My dream is to eliminate PSK from all the networks I care about/am responsible for, but it's really challenging to deploy 802.1X in anything but a fully managed enterprise (and also hard when you also have random other IOT/etc. type devices; usually the "important" ones you can just put onto wired network, and the unimportant ones go onto dedicated psk, but it's still a pain. Still hate it all less than captive porta…

Agreed all around, it'd be really nice if there were better general standards for friendly ways to deploy and utilize 802.1x. IOT is definitely a big hold up there, support is quite spotty even amongst new major device manufacturers. I recently was asked to deploy a bunch of Nest smoke alarms at a business for example (they are genuinely nice, and the testing I've seen indicate their dual wavelength photoelectric sensors do a very good job), and they don't support it. But even outside of IOT I'm quite surprised sometimes by mainstream devices that make it more of an effort then it needs to be, such as Chromebooks. I was surprised mainly because one place user/pass auth for WiFi isn't at all uncommon is colleges, and I'd have assumed students there were a significant enough general market to be worth more attention. On a Mac 802.1x is all a single flow at the simplest level, select the network, enter the credentials, it'll ask about the cert if it's self-signed, and that's it. Compare to the Chromebook procedure [1], it's not like it's horribly involved but why the whole separate cert procedure?

Granted, authentication in general remains a lot of spaghetti across the entire industry. I don't think there is a lot of relief overall on the horizon, though at least in some areas like with WebAuthn there is hopeful progress. Maybe progress in separate areas will ultimately make a foundation that can be further expanded.

1: https://support.google.com/chromebook/answer/1047420?hl=en

Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#36

Post by yrro »

gipsies wrote: post #21
zamadatix wrote: post #4

Downgrade attacks: WPA3 has a transitional mode which allows legacy WPA2 clients to connect. In this mode legacy WPA2 security issues are still present. Is this really a discovery or a given? How is WPA3 supposed to protect against it without requiring either WPA2 clients to be upgraded to support WPA3 security fixes (in which case you don't need WPA2 support anymore anyways) or without dropping support for transitio…

If we look at the paper then these remarks are all discussed: - Defending against downgrade attack: "A client should remember if a network supports WPA3-SAE. That is, after successfully connecting using SAE [..] the client must never connect to this network using a weaker handshake". The Google Pixel 3 is thankfully already doing this, but others aren't. So perfectly preventable, and something the Wi-Fi Alliance coul…

Hmm, so I can't have several APs sharing the same ESSID with the newer ones supporting WPA3 and the older ones WPA2?

Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#37

Post by gipsies »

zamadatix wrote: post #31
gipsies wrote: post #21

Earlier quoted context omitted.

If we look at the paper then these remarks are all discussed: - Defending against downgrade attack: "A client should remember if a network supports WPA3-SAE. That is, after successfully connecting using SAE [..] the client must never connect to this network using a weaker handshake". The Google Pixel 3 is thankfully already doing this, but others aren't. So perfectly preventable, and something the Wi-Fi Alliance coul…

"A client should remember" just transfers things to first trust attacks, if you want to do it right you'd have to make sure you add the network to the device as WPA3 only from the get go. Side channel attacks, sure, the standard could also have just said "don't be vulnerable to side channel attacks when generating secure data" along with everything else you should do to make a secure system. Does it really matter how…

I again feel that most of these points are all discussed in the paper. Trust-on-first-usage is also used in SSH. Attack uses spoof MAC addresses, hard to rate-limit that. Modern crypto should be designed to reduce chance of implementation flaws. Paper concludes that WPA3 is still better than WPA2. Most attacks are on WPA3's Dragonfly. Etc. The most practical attacks are downgrades to WPA2 though, so the press might focus too much on that..

Re: Serious flaws leave WPA3 vulnerable to hacks that steal Wi-Fi passwords

#39

Post by tinus_hn »

zamadatix wrote: post #4

Downgrade attacks: WPA3 has a transitional mode which allows legacy WPA2 clients to connect. In this mode legacy WPA2 security issues are still present. Is this really a discovery or a given? How is WPA3 supposed to protect against it without requiring either WPA2 clients to be upgraded to support WPA3 security fixes (in which case you don't need WPA2 support anymore anyways) or without dropping support for transitio…

At least with wpa2 there are devices that perform DOS by just telling devices to disassociate themselves from networks. These are (illegally) used by hotels to force you to use their paid Wi-Fi. Easier than filling all the channels or overloading an AP CPU.
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