| ▲ | Your TV can see through walls(maurycyz.com) |
| 101 points by Curiositry 4 hours ago | 34 comments |
| |
|
| ▲ | numlock86 2 hours ago | parent | next [-] |
| Wait for people to learn about that you can listen in virtually anywhere through fiber-optic cables, as sound waves are enough to redirect the light in the cable to a measurable degree by "bending" the cable itself. Special devices to filter these variances out and transform them back to audio signals are a thing. It's only per line though, as any repeating device will just output a new cleaned up signal again. Oh well, there have always been ways to snoop on someone like that. Back in the day it was CRTs emitting measurable waves through the neighborhood, with some papers even going as far as restoring the displayed image through a wall. Nowadays it's fiber and WiFi, and those seem to be much easier to work with even. Plus everyone carries a device that is tracked by their mobile provider's cell network. shrug |
| |
| ▲ | ClikeX 17 minutes ago | parent | next [-] | | You can also listen for audio simply by measuring any vibrating surface with a laser. Which goes all the way back to the late 40s, used by the USSR. | Fun fact, it was invented by Leon Theremin. The inventor of the Theremin. | |
| ▲ | kurthr an hour ago | parent | prev | next [-] | | Just toss a doppler laser interferometer on a window, mirror, etc. At least with fiber-optics you need physical access. Single mode (I think that's most of FTTH) is pretty insensitive to vibration and hard to localize so you'd really have to install something. | | |
| ▲ | andai 11 minutes ago | parent [-] | | Ah, but of course. How could I forget about my trusty pocket doppler laser interferometer! |
| |
| ▲ | euroderf 9 minutes ago | parent | prev [-] | | So when AI takes over the world, it will have a convenient tap into every living space of every hoomin. Lovely. |
|
|
| ▲ | armcat an hour ago | parent | prev | next [-] |
| Several years back we actually made use of the principle mentioned in this post, to more systematically count traffic on the roads [1]. In our case we used LTE/4G radio, and we could even estimate the direction of travel, as well as the type of traffic (pedestrian, small vehicles, large vehicles). It was more accurate than Google Maps because it was independent of the moving phone, i.e. it was "sensing the obstacles in the environment". [1] "Traffic Flow Estimation using LTE Radio Frequency Counters and Machine Learning", https://arxiv.org/abs/2101.09143 |
|
| ▲ | swerner 3 hours ago | parent | prev | next [-] |
| As anyone observed who had a TV with just basic analog terrestrial antennas, before cable and satellite dishes - it does make a difference to the signal, when and where you stand and countless pieces of physical comedy in TV shows incorporated that. |
| |
|
| ▲ | 1e1a 2 hours ago | parent | prev | next [-] |
| See these for a very low cost (<$10) method for observing WiFi and some LTE spectra: https://news.ycombinator.com/item?id=49922674 https://espargos.net/espsdr/ |
|
| ▲ | fzeindl 3 hours ago | parent | prev | next [-] |
| Amazing book about similar topics: “Silence on the wire” by Michal Zalewski https://www.amazon.de/Silence-Wire-Passive-Reconnaissance-In... |
|
| ▲ | ThePumpkinGod 3 hours ago | parent | prev | next [-] |
| So, a bad actor can now know when I'm at my house or not, I'm sure that's fine and won't be problematic |
| |
| ▲ | ClikeX 12 minutes ago | parent | next [-] | | Bad actors, and any WiFi capable hardware in your house. There's an official spec for it[1], and some routers already have the option built in. I remember seeing papers about this over 10 years ago, someone at MIT did it for a paper. Philips Hue also has it built in to their newer lights, where they measure the Zigbee signals. They call it MotionAware[2]. Basically anything with an antenna and a bit of compute is able to do this now. [1] IEEE 802.11bf-2025
[2] https://www.philips-hue.com/en-hk/support/article/motionawar... | |
| ▲ | st_goliath 6 minutes ago | parent | prev | next [-] | | > So, a bad actor can now know when I'm at my house or not. A bad actor who wants to act on that information can just wait near your house on a workday morning and watch you leave. | |
| ▲ | gruez an hour ago | parent | prev | next [-] | | Can't they already do that by snooping on ARP traffic on your home LAN? Failing that, if they can get whatever shitty wifi chipset they're using to enter promiscuous mode, they can also sniff all STAs that are in the vicinity, and with some ML they can probably figure out which MAC belongs to your phone. | |
| ▲ | rightnutwingjob 3 hours ago | parent | prev | next [-] | | Even having three security cameras around the perimeter of your house can allow quite precise location and activity detection inside the house via their audio steams. Those mics can be quite sensitive. | | |
| ▲ | ThePumpkinGod 3 hours ago | parent | next [-] | | I don't have security cameras in my house but that's actually interesting to see how things most people have in their house can (and does?) used to spy on them. | |
| ▲ | motbus3 an hour ago | parent | prev | next [-] | | Yes. But depending who is doing the work they can just see what Bluetooth devices are around each hour of the day too...
It sucks that everything we have seems to be usable against us | |
| ▲ | SlightlyLeftPad an hour ago | parent | prev [-] | | Really? They can’t seem to pick up a conversation happening directly in front of them. |
| |
| ▲ | cowlevel 3 hours ago | parent | prev [-] | | They already knew this from your cell phone not being in airplane mode. | | |
| ▲ | ThePumpkinGod 3 hours ago | parent | next [-] | | If I ever try to hide (which is probably impossible at this time and age), I will probably just break my phone not like I can use it anyways every single act in it sends data to too many places to count. | | |
| ▲ | guax an hour ago | parent [-] | | I assume the problem is still tracing and association. So long as there is no direct link between you and the device, there is no saying if that is you or not. So grabbing a used phone via cash transaction from someone and only turning it on and using outside of your usual locations could be enough to have it being "anonymous". Then, using a vpn or other proxy that hides your network can make you very hard to find, so long as you don't associate with your real identity in any substantial form. The danger with these technologies is not when they allow to precise track you once your general vicinity is known, that was always possible by putting some goons after you. General mass surveillance that is constantly tagged is the problem, flock, PRISM and the other stuffs. | | |
| ▲ | ClikeX 7 minutes ago | parent [-] | | There was a TV show in the Netherlands, called Hunted I believe. Contestants had to go on the run and avoid getting caught by the hunting team without doing anything illegal. Or staying to long in a single place, so no camping in the middle of a park (which would technically be illegal anyway). Long story short, barely anyone got anywhere. Because simply doing an ATM transaction to get the cash already triggered the signal where they were. Not to mention the amount of government owned cameras. As well as being in proximity of anyone still online. Complete anonymity is virtually impossible, depending on the country. |
|
| |
| ▲ | lencastre 3 hours ago | parent | prev [-] | | there is always the risk of the isolated Faraday caged house |
|
|
|
| ▲ | thopterek 3 hours ago | parent | prev | next [-] |
| Thank you for more paranoia |
| |
| ▲ | rightnutwingjob 3 hours ago | parent | next [-] | | π RuView turns commodity WiFi signals into real-time spatial intelligence, vital sign monitoring, and presence detection — all without a single pixel of video. https://github.com/ruvnet/RuView | | |
| ▲ | inexcf an hour ago | parent [-] | | Just so anyone who reads this knows: This is a well known SCAM repo. The install instructions are incomplete and when you manage to get it running you will realize the data it produces is just random except for pre-recorded simulated data. If you check youtube for it you will find hundreds of completely AI generated Videos with not one of them showing the actual thing working. And all while trying to sell you some hardware. https://github.com/deletexiumu/wifi-densepose " SCAM ALERT: Technical audit reveals this project is a non-functional AI-generated facade with fake CSI data, no trained models, and suspected star inflation" |
| |
| ▲ | neverbeenasked an hour ago | parent | prev [-] | | yeah, now I gotta unplug TV too |
|
|
| ▲ | gbxyz 3 hours ago | parent | prev | next [-] |
| See also: Van Eck Phreaking https://en.wikipedia.org/wiki/Van_Eck_phreaking |
| |
|
| ▲ | darkwater 2 hours ago | parent | prev | next [-] |
| Now, about the wifi part, why isn't there an Home Assistant extension that detects already room presence magically exploiting all of this?? |
| |
|
| ▲ | walrus01 3 hours ago | parent | prev [-] |
| see also, presence detection of humans via wifi signals: https://arxiv.org/html/2308.06773v2 |
