I often have a dev server running bound to 0.0.0.0 as it makes debugging easy at home on the LAN, but then if I connect to a public WiFi I want to know that I am secure and the ports are closed. "Block all incoming connections" on macOS has failed me before when I've tested it.
Just FYI: LittleSnitch pre-resolves DNS entries BEFORE you click `Accept/Deny`, if you care & understand this potential security issue. Your upstream provider still knows whether you denied a query. Easily verifiable with a PiHole (&c).
I liken the comparison to disk RAIDs: a RAID is not a true backup; LittleSnitch is not a true firewall.
You need isolated hardware for true inbound/outbound protection.
This also feels like an exfil route? Are DNS queries (no tcp connect) logged/blocked?
No, not with LittleSnitch (neither in/out-bound).
When you see the LittleSnitch dialogue (asking to `Accept/Deny`), whatever hostname is there has already been pre-resolved by upstream DNS provider (does not matter which option you select). This software pares well with a PiHole (for easy layperson installs), but even then is insufficient for OP's attack.
Summary: https://www.ndss-symposium.org/ndss-paper/airsnitch-demystif... (hat tip: https://news.ycombinator.com/item?id=47167975)
however, most people will read "breaks wi-fi encryption" and assume that it means that someone can launch this attack while wardriving, which they cant.
As a former wardriver (¡WEPlol!), it only makes this more difficult. In my US city every home/business has a fiber/copper switch, usually outside. A screw-driver and you're in.
Granted, this now becomes a physical attack (only for initial access) — but still viable.
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>the next step is to put [AirSnitch] into historical context and assess how big a threat it poses in the real world. In some respects, it resembles the 2007 PTW attack ... that completely and immediately broke WEP, leaving Wi-Fi users everywhere with no means to protect themselves against nearby adversaries. For now, client isolation is similarly defeated—almost completely and overnight—with no immediate remedy available.
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I think the article's main point is that so many places have similarly-such-unsecured plug-in points. Perhaps even a user was authorized for one WiFi network segment, and is already "in" — bless this digital mess!
- must not be accessible because their services don't use authentication/encryption
- and share a wifi with potential attackers
is just not that large.
They exist, but the vast majority runs in places that don't care about security all that much.
This should be a signal to fix the two things I mention, not to improve their wifi/firewall security.
Also client isolation is not considered "needed" in home/SOHO networks because this kind of attack is kinda assumed out of scope; it's not even tried to address this. "If you give people access to your wifi, they can fuck with your wifi devices." This should probably be communicated more clearly, but any claims on this attack re. home networks are junk.
It’s very difficult to have too much network security.
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.
Still an interesting attack though.
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...
I haven’t paid attention to one in a while but I seem to remember the need to authenticate with the guest network using Xfinity credentials. This at least makes it so attribution might be possible.
I turn WiFi mine off and use my own WiFi ap.
To prevent malicious Wi-Fi clients from attacking other clients on the same network, vendors have introduced client isolation, a combination of mechanisms that block direct communication between clients. However, client isolation is not a standardized feature, making its security guarantees unclear. In this paper, we undertake a structured security analysis of Wi-Fi client isolation and uncover new classes of attacks that bypass this protection. We identify several root causes behind these weaknesses. First, Wi-Fi keys that protect broadcast frames are improperly managed and can be abused to bypass client isolation. Second, isolation is often only enforced at the MAC or IP layer, but not both. Third, weak synchronization of a client’s identity across the network stack allows one to bypass Wi-Fi client isolation at the network layer instead, enabling the interception of uplink and downlink traffic of other clients as well as internal backend devices. Every tested router and network was vulnerable to at least one attack. More broadly, the lack of standardization leads to inconsistent, ad hoc, and often incomplete implementations of isolation across vendors. Building on these insights, we design and evaluate end-toend attacks that enable full machine-in-the-middle capabilities in modern Wi-Fi networks. Although client isolation effectively mitigates legacy attacks like ARP spoofing, which has long been considered the only universal method for achieving machinein-the-middle positioning in local area networks, our attack introduces a general and practical alternative that restores this capability, even in the presence of client isolation.
>The most powerful such attack is a full, bidirectional machine-in-the-middle (MitM) attack, meaning the attacker can view and modify data before it makes its way to the intended recipient. The attacker can be on the same SSID, a separate one, or even a separate network segment tied to the same AP. It works against small Wi-Fi networks in both homes and offices and large networks in enterprises.
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I wardrove back in the early 2000s (¡WEP lol!). Spent a few years working in data centers. Now, reasonably paranoid. My personal network does not implement WiFi; my phone is an outgoing landline; tape across laptop cameras, disconnected antenna; stopped using email many years ago...
Technology is so fascinating, but who can secure themselves from all the vulnerabilities that radio EMF presents? Just give me copper/fiber networks, plz.
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>the next step is to put [AirSnitch] into historical context and assess how big a threat it poses in the real world. In some respects, it resembles the 2007 PTW attack ... that completely and immediately broke WEP, leaving Wi-Fi users everywhere with no means to protect themselves against nearby adversaries. For now, client isolation is similarly defeated—almost completely and overnight—with no immediate remedy available.
Thank you for your recommendation - it be crazy up in here (head, country, world).
Great movie.
Are you suggesting The Conversation is even better?! So excited for tonight's showtime — I'll make an updated reply here, tomorrow morning (with my viewreport).
On WPA3/SAE this is more complicated: the standard supports password identifiers but no device I know of supports selecting an alternate password aside from wpa_supplicant on linux.
Has China become so prominent in security research?
"If the network is properly secured—meaning it’s protected by a strong password that’s known only to authorized users—AirSnitch may not be of much value to an attacker."
This is likely not a big deal for your home network, if you only have one network, but for many enterprise setups probably much worse.
These attacks are not new: the shocking thing here that apparently a lot of enterprise hardware doesn't do anything to mitigate these trivial attacks!
Exactly.
Essentially everyone with the SSID on multiple access point MAC addresses can get pwned.
Neighhood hackers drove me to EAP TLS a few years ago, and I only have it on one frequency, so the attack will not work.
The mitigation is having only a single MAC for the AP that you can connect to. The attack relies on bouncing between two. A guest and regular, or a 2.4 and 5, etc.
I need to research more to know if they can read all the packets if they pull it off on EAP TLS, with bounces between a 2.4 and 5 ghz.
It is a catastrophic situation unless you are using 20 year old state of the art rather that multi spectrum new hotness.
It might even get folks on a single SSID MAC if they do not notice the denial of service taking place. I need to research the radius implications more. TLS never sends credentials over the channel like the others. It needs investigation to know if they get the full decryption key from EAP TLS during. They were not using TLS because their tests covered Radius and the clients sending credentials.
It looks disastrous if the certificates of EAP TLS do not carry the day and they can devise the key.
That is my take.
My concern is doing it asynchronously against things when no one is watching.
Basically it takes turn being the client and the AP both so that it can get the traffic from both. It is an evil twin attack doubled.
It might have broken EAP TLS.
If your wifi is off when you are not using it and you are not getting denial of serviced while using it and you have only one Mac for your SSID, this attack is not occuring.
Some people also have passwords easy to break. Friend of mine literally had "hunter22" as WiFi password.
You still have to be able to authenticate to some network: the spoofing only allows users who can access one network to MITM others, it doesn't allow somebody with no access to do anything.
In practice a lot of businesses have a guest network with a public password, so they're vulnerable. But very few home users do that.
Getting authentication to the network is not the worst part. That can be found quickly, but is bad if you do not monitor.
The bad part is getting the encryption keys and sniffing all the traffic flowing via the wifi network. They could do that passively without even being authenticated anymore.
Until this attack there was no documented way to get a radius shared key since it is never sent via the wifi.
They have MITM both sides. The question in my mind is whether it can get useful decryption keys over asynchronous time frames. E.g. They denial of service MITM the tablet while no one is watching and then sit and sniff my laptop without me knowing it without having to authenticate anymore.
It clearly broke Peap etc. by impersonation rather than cracking because they got credentials and could reuse them later. Does it work for certificates only...
bell-cot•1h ago
OTOH... with the recent journalistic scandal at Ars Technica, perhaps Dan should have made sure that he spelled "Ubiquity" correctly? (5th para; it's correct further down.)
John23832•1h ago
I don't even think most editors would know the difference. That's the problem with using corruptions of real words as your name.
bookofjoe•1h ago
pinkmuffinere•1h ago
g-b-r•36m ago
I only read his articles occasionally, but they always impressed me favorably; this one instead... the paper is probably clearer even for less technical people.