Your WiFi Can See You

https://mrereports.substack.com/p/your-wifi-can-see-you

by nunodio • 3 years ago

195 89 3 years ago

mrereports.substack.com

lusus_naturae• 3 years ago

Dina Kitabi was doing wifi sensing before 2017: https://people.csail.mit.edu/dina/publications.html?tag=syst...

femto• 3 years ago

No doubt that work would have fed into the development of the WiFi 802.11bf standard.

xahrepap• 3 years ago

I feel like “putting wifi in my home” is similar to “putting bodies that emit heat in my home”. Neither of which implicitly grant law enforcement to come and observe either through the walls of my home.

I am not a lawyer, nor am I familiar with the SCOTUS case referenced in the article. But I really hope it is precedent enough to make any judge throw out any such violations without any hassle.

matheusmoreira3• 3 years ago

Still enables parallel construction. They can illegally search and surveil you without your knowledge and there's not much anyone can do about it. They can't submit any findings as evidence but they can totally anonymously tip off other authorities or something.

It must be physically impossible to violate our privacy or it doesn't work.

XorNot2• 3 years ago

Parallel construction only works if you've actually committed a crime and left evidence somewhere it can be plausibly found - i.e. "a random search of the public woods near your area found a shallow grave, and tire-tracks matching your car" - but the search was conducted because what actually happened was you were telling a guy "yes I definitely killed Tony and buried him in the woods".

People keep using the term as though it implies some legal means of fabricating evidence against someone: which is ridiculous because if you're willing to fabricate evidence, you don't need to actually find any.

It's also worth noting that in the case of incidental wifi surveillance, it's likely the plain-sight doctrine would apply: if you're being imaged and positioned by broadcasts you yourself are making and nearby devices can receive, then this would be ruled in plain sight and rightly so (I can't stop my routers and devices from detecting nearby devices as part of interference avoidance).

scrps3• 3 years ago

The one upside to this being based on open standards also means that there is no reason this tech can't be used against say, police, politicians, executives.

Though I'd like to actually look at how it is practically done first, for all I know this could require more than just access to an AP. This is not my area of expertise so maybe someone that is an expert can confirm my intuition that beamforming even on enterprise grade access points isn't locative (if that is the right word?) enough on it's own, I'd imagine this would require some type of kit to be deployed in order to accurately map a room?

Also plaster walls or at least my plaster walls seem to be great at blocking anything over 2.4GHz :\

sambazi• 3 years ago

It must be physically impossible to violate our privacy or it doesn't work.

it has to be expensive enough in order to not be worth it.

mk_stjames2• 3 years ago

If someone is worried that their government could be flashing the firmware of their WiFi router to use the beamforming antennae of the router to track them walking around their home....

Then they should be way more worried that their government is using any access to their wifi router at all. Like, you got way bigger things to worry about at that point, right?

There are a million surveillance side-channels that could be used to build profile-able information about what is happening inside a home from the outside. The concern isn't that those things are possible (they always will be) the concern should be that there are authorities who could be (mis)using such avenues and not explicitly being disallowed in the first place.

ARandomerDude• 3 years ago

I disagree. The trajectory of technology generally is:

possible -> prototype -> product -> common -> common and cheap

If Wi-Fi surveillance were to become common and cheap, other methods would be produced to make data harvesting common and cheap to the surveillance state/bigco. The best way to avoid that dystopia is to safeguard it early in the process.

momirlan• 3 years ago

i don't think any safeguards will protect us from evils brought about by technology - it evolves too fast already for the society to catch up .

mk_stjames2• 3 years ago

What I'm trying to get at is, even if this type of Wifi surveillance becomes commong and cheap, it still requires access at a low level to the wifi router itself. Which should be hands-off in the first place. It's like having cameras in your house on your local network... if the police could legally hack into your network, they could watch you on the cameras to see if you are committing crimes! But... the point is they shouldn't be able to do that, regardless if you have the cameras or not... the line is drawn at the access.

Same thing there. It shouldn't matter if the tech is possible, produced, cheap, and installed in your home.... it's all moot if the act of the surveillance isn't followed through. We need to work towards ways to prevent the acts themselves, as we simply aren't going to be able to prevent the possible sidechannel attacks from being possible. They are always possible.

akira2501• 3 years ago

You are living in that dystopia already, then, and your efforts are equivalent to plugging a hole in the grand dam with your finger.

enragedcacti• 3 years ago

The linked paper "Et Tu Alexa?" uses a single smartphone positioned outside of the property

We show that just by sniffing existing WiFi signals, an adversary can accurately detect and track movements of users inside a building. This is made possible by our new signal model that links together human motion near WiFi transmitters and variance of multipath signal propagation seen by the attacker sniffer outside of the property.

matheusmoreira3• 3 years ago

Then they should be way more worried that their government is using any access to their wifi router at all.

We should be worried about ISPs too. They give themselves access to their customer premises equipment. I had to hack their router to put it into bridge mode and then use another router with software I control to connect.

edgyquant• 3 years ago

No, what could be a bigger worry than an omnipresent government intent on total control?

psd12• 3 years ago

Cancer.

ilaksh• 3 years ago

You don't think that there is some agency like the NSA or such that can access your full Google search history and location in real time? There might even be some individuals with access that doesn't even require search warrants or anything.

devjab• 3 years ago

I’m curious as to which government you think isn’t going to use surveillance tools on you, even if they aren’t exactly legal. I mean, after Echelon we still had the tinfoil disbelief to fall back on, but in a post-Snowden world it’s hard to imagine why you would think your government wouldn’t do this.

You’re not exactly wrong in that you should also be worrying about: Boundless Information, Bullrun, Carnivore, DSCNet, Fairview, ICREACH, Magic Lantern, Main Core, Mainway, Media Monitoring Services, Muscular, Mystic, Nationwide Suspicious Activity Reporting Initiative, NSA Ant Catalog, PRISM, Room641A, Sentry Eagle, Special Collection Service, Stellar Wind, Tailored Access Operarions, Turbulence, and, X-Keyscore if you’re American. But that doesn’t mean you shouldn’t also worry about this, just as much.

sdrawdes2• 3 years ago

Reminds me of The Thought Emporium's camera that can see WiFi. https://youtu.be/g3LT_b6K0Mc?si=PRtkeXRqq8UmhpC9

TechBro8615• 3 years ago

CNLohr made a similar project three years before that: https://youtube.com/watch?v=aqqEYz38ens

I know this stuff is dystopic, but I personally find it really cool. That said, I also disable WiFi and prefer ethernet wherever possible...

gorgoiler• 3 years ago

Imaging like this is like scanning a scene with a one pixel camera. Cameras use a lens to focus an image onto a plane, and the plane has multiple sensors. What would that device look like for microwaves?

(Welcome to HN!)

yoru-sulfur2• 3 years ago

A number of years ago I worked for a company that developed a home security product using this kind of tech: https://www.cognitivesystems.com/

system2• 3 years ago

Does it work as advertised?

yoru-sulfur2• 3 years ago

I haven't worked there for years, so not sure what has changed since I was there but at least at the time it was decent. It could reliably detect movement, but was getting triggered by pets and such. They were working on solutions to that when I left.

kibwen• 3 years ago

Apropos of nothing, a conductive mesh with 1/2" holes suffices to block 2.4 Ghz signals, while 1/4" holes suffice to block 5 Ghz signals. https://www.homedepot.com/s/hardware%20cloth

aidenn0• 3 years ago

Hah, I remember having a tiny condo and was unable to get wifi throughout it because it was constructed with a metal-mesh backing[1] instead of wooden lath for the plaster. Was like a 60db drop putting a device on the opposite side of a wall made from one of these.

1: Kind of like this https://www.homedepot.com/p/Gibraltar-Building-Products-3-4-...

tetsuhamu• 3 years ago

Yes!

We build walls out of materials opaque to visible light. Our walls are basically windows for wifi, so make them opaque! It's all EMR

cglan• 3 years ago

Are there any home solutions to wifi sensing/location sensing at home for diy iot purposes?

toomuchtodo• 3 years ago

https://wrlab.github.io/Wi-ESP/

https://github.com/StevenMHernandez/ESP32-CSI-Tool

sdrawdes2• 3 years ago

https://github.com/FOULAB/Project-COGSWORTH

SEJeff• 3 years ago

Tomographic detection has been around for some time. There was a company that commercialized this and had a more or less real-time Harry Potter style “Marauder’s Map” of your home for a security system but they did a lousy job commercializing it.

See a crappy demo of the Xandem solution: https://youtu.be/0lnfOnZD6d8?si=1QqIO0mvHsP4mj5n

Their Xandem home product was fantastic, though failed commercially due to the price.

metadat• 3 years ago

Related discussion 7 days ago:

WiFi can read through walls

https://news.ycombinator.com/item?id=37469920 (171 comments)

newhouseb• 3 years ago

I'm a little skeptical of the paper in question: https://arxiv.org/pdf/2301.00250.pdf

If you look at the training and test set info:

We report results on two protocols: (1) Same layout: We train on the training set in all 16 spatial layouts, and test on remaining frames. Following [31], we randomly select 80% of the samples to be our training set, and the rest to be our testing set. The training and testing samples are different in the person’s location and pose, but share the same person’s identities and background. This is a reasonable assumption since the WiFi device is usually installed in a fixed location. (2) Different layout: We train on 15 spatial layouts and test on 1 unseen spatial layout. The unseen layout is in the classroom scenarios.

Depending on how they selected various frames -- let's just say it was random -- the model could have learned something to effect of "this RF pattern is most similar to these two other readings I'm familiar with" (from the surrounding frames) and can therefore just interpolate between the resulting poses associated with those RF patterns (that the model has compressed/memorized into trained weights).

If you look at the meshes between the image ground truth and the paper's results, you'll see that they are strikingly similar. I find this also suspect because WiFi-band RF interacts a lot more with water than with clothes and so you would expect the outline/mesh to get the "meat-bag" parts of you correct but not be able to guess the contours of baggy clothes. That is... unless it has memorized them from the training set.

est2• 3 years ago

Also

It should be noted that many WiFi routers, such as TP-Link AC1750, come with 3 antennas, so our method only requires 2 of these routers.
WiFi-based perception is based on the Channel-state-information (CSI) that represents the ratio between the transmitted signal wave and the received signal wave. The CSIs are complex decimal sequences that do not have spatial correspondence to spatial locations

AFAIK, access to raw CSI data is not available on consumer routers. You need specific FPGA/SDR boards which happens to speak the WIFI 2.4G/5G protocol.

There are some open sources efforts such as https://github.com/open-sdr/openwifi

transpute4• 3 years ago

FPGA/SDR boards

Custom firmware is available for existing WiFi radios, e.g. sub-$20 ESP32 WROOM.

Previous HN discussion: https://news.ycombinator.com/item?id=34480760

jxj• 3 years ago

We do even further. If we use openwifi as a router in home, it can fuzz the CSI and destroy those sensing method: https://github.com/open-sdr/openwifi/blob/master/doc/app_not...

nomilk2• 3 years ago

The wifi router sees you (a bit like a mini radar), but someone outside your premises would still have to hack the router? Or do ISPs already have that access?

Also curious to know how far wifi routers 'see'? If it's more than a few meters there could be more potential surveillance by wifi router than by cctv!

srejk• 3 years ago

Look up TR-069. Always use your ISP-supplied router in bridge/modem mode only.

tetris112• 3 years ago

https://en.wikipedia.org/wiki/TR-069

Eye-opening indeed..

nomilk2• 3 years ago

IIUC:

- 'TR-069' is the name of a protocol by which (most) ISPs operate

- It gives ISPs the rights/ability to interact with your devices remotely (under the guise of maintenance and remote troubleshooting)

- This isn't something that's going to happen one day far in the future; it already applies to most(/all?) routers currently in use in countries whose ISPs abide by the protocol

So ISPs can already see inside customer homes?! (since they can already access the data necessary to use the WiFi device as a makeshift imaging system? - wowzers!

tetris112• 3 years ago

Or do ISPs already have that access?

"In order to comply with DOCSIS4.2 regulations, we require anonymous WiFi telemetry for 5GhZ or higher due to safety. You can disable this at any time and use 2.4GhZ."

Or some such. Just give it time.

neets• 3 years ago

I thought they made that up in that Person Of Interest[1] Episode, seems like they were just ahead of the curve on tech

1. https://www.imdb.com/title/tt1839578/

CommieBobDole• 3 years ago

Looking at the source articles, this seems to require specialized equipment and large antennas that are fairly close to whatever is being imaged. So unless there's been some sort of breakthrough, this is not a case of "someone could hack your router and see you in your home".

jaza• 3 years ago

The article is saying "not yet, but soon, sooner than you think".

transpute4• 3 years ago

Matt Damon and Ben Affleck's Incorporated (2017) TV series, https://www.youtube.com/watch?v=t7eKEHhSw00 & https://en.wikipedia.org/wiki/Incorporated_(TV_series), includes thought experiments on future workplace surveillance.

The series takes place in a dystopian Milwaukee in the year 2074, where many countries have gone bankrupt .. In the absence of effective government, powerful multinational corporations have become de facto governments, controlling areas called Green Zones. The remaining territories are called Red Zones, where governance is weak or non-existent.

Consumer Wi-Fi 7 Sensing routers (estimated to arrive in 2024 with IEEE 802.11bf) can generate 3D images of human activity through the walls/floor/ceiling of homes and business, profiling human position, movements, breathing, keystrokes, emotion and more, https://news.ycombinator.com/item?id=34480760.

After standardization by IEEE in consumer routers, which remote parties would be interested in WFH WiFi Sensing Analytics? How could regulators, employers, employees and home-builders respond? Remote, through-wall, X-Ray vision monitoring can be entirely passive when there is ambient WiFi traffic, e.g. reflections from routers inside targeted urban buildings of interest. This has been possible for more than a decade, using either expensive LE equipment or low-cost DIY/RF/hacker toolsets. Will IEEE standardization of Wi-Fi 7 Sensing give X-ray vision superpowers to every neighbor?

On a positive note, there is some commercial interest in Li-Fi for wireless data transfer via optical light, so that data transfers will stop at a perimeter established by traditional walls. Until then, aluminum radiant barrier, conductive paint, RF shielding drywall (e.g. QuietRock) or metal mesh can reduce unwanted inbound/outbound RF signals. For temporary shielding of a room, consider a Zipwall-like tension pole frame supporting a cube of aluminum radiant barrier (USD $0.25 per square foot), plus shielded air ventilation.

swader999• 3 years ago

I just have a house full of manicans. Bonus, I never get lonely.

Mistletoe• 3 years ago

It’s enough to make you want to sleep in a Faraday cage coffin every night. A privacy vampire.

raavikant• 3 years ago

How?

arsome• 3 years ago

If using an FLIR camera is considered an unreasonable search without a warrant, I fail to see how this wouldn't be too.

dang• 3 years ago

Recent and related:

WiFi can read through walls - https://news.ycombinator.com/item?id=37469920 - Sept 2023 (171 comments)

red-iron-pine2• 3 years ago

more like "Wifi can read big metal Home Depot sign letters through walls from reasonably close"

good proof of concept tho, and a cool video

Communitivity2• 3 years ago

I wonder if this will cause an interest in in Faraday Cage walls: outer wall sheetrock with a copper wire mesh support, with a ground to prevent re-radiating. You'd also need to have the same mesh on the house roof and attic walls. Copper would be best for conductivity. The mesh holes would need to no greater than 5mm to block 2.4Ghz and 5Ghz. This is rounded down to the nearest mm from the equation:

   hole size (m) = speed (m/s) x frequency (Hz) 
   (.0599 = 299,792,458 * 5,000,000,000)

The better the conductivity of the metal the thinner the thickness can be. It's differences between 10s of microns though, so in practical terms thin copper fire should work. Even thin steel wire should work.

Your biggest leakage problem would be doors and windows. Window screens sized to stop mosquitos (1.2mm hole size) will help with this, for the windows. Metal screen doors should help.

This won't prevent all leakage, but should prevent most of it.

danw1979• 3 years ago

Leakage doesn’t seem to be the problem that is being explained here: it’s internal sensing within the home by existing wifi devices.

Communitivity2• 3 years ago

It doesn't need to be your wifi devices, it could be your neighbor's, if you're in a townhouse or your house is close enough.

But I agree with another commenter: if they've hacked your wifi router then you have bigger problems, as they've likely hacked all your devices then.

gloosx3• 3 years ago

I don't understand, why the author's concern is focused around surveillance through wifi. The routers are private devices, so if secured properly, what kind of backdoor a third party could use to take imagery of your house insides?

Law enforcement for decades has used commercial cellular networks to spy on people, and with the modern 5g technologies these surveillance suites are very well developed and able to see EVERYONE at scale with centimeter precision.

SergeAx3• 3 years ago

Amazon Alexa, Google Nest. BTW, every smatphone has a WiFi.

gloosx3• 3 years ago

every smartphone can report your exact location anyway, for me 5g is a much bigger privacy concern than wifi could ever be.

SergeAx3• 3 years ago

I am a bit concerned about the source. It seems like a conspiracy theories head-to-toes, see their other publications.

Stem0037• 3 years ago

It seems imperative to establish potential safeguards to prevent misuse of this technology.

Your WiFi Can See You

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