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Why Snowden Asked Visitors in Hong Kong to Refrigerate Their Phones
- pilsetnieks 13y agoShouldn't a microwave oven be the perfect household Faraday cage? It certainly has the shielding to contain 2.4 GHz waves, so the 800, 900, 1800, 1900 MHz cannot be that far off.
- marshray 13y agoLess soundproofing.
- human_error 13y agoHow about putting phones inside the microwave and then putting microwave inside the fridge?
- marshray 13y agoI favor putting the phone in the martini shaker, and the shaker inside the dishwasher while washing a big load of clanky dishes.
- deleted 13y ago[deleted]
- refurb 13y agoGood question. The mesh size of the Faraday cage should be less than 1/2 the wave length of the RF radiation. At 2.4 GHz, the wavelength is ~125mm, and the mesh size of your typical microwave is a few mm. With the lower frequency of the cellular bands, you'd expect the microwave to work pretty well.
- marshray 13y agoThere's also the gap around the door, which is often poorly fitting on older worn-out units. Still, the phone could be recording audio to upload at a later time. Audio storage capacity isn't likely to be a problem on modern phones.
- jlgreco 13y agoConsidering how much trouble microwave ovens have given me with wifi in the past, I would not place much confidence with them.
- e12e 13y agohttp://xkcd.com/654/ http://xkcd.com/654/
- PencilAndPaper 13y agoSo the mic in your phone can be used as a bug when you arent using it?
- gambiting 13y agoYes. On some phones even when its off.
- kllrnohj 13y agoIf the phone is off it cannot be remotely accessed, and thus cannot be used as a remote listening device.
- TylerE 13y agoHow do you know if it's really off? Just because the leds arne't lit and the screen is off is no guarantee.
- kllrnohj 13y agoThey sell these devices for $20 or so called "multimeters" that let you measure this. Also there's the pretty fucking obvious fact that the battery suddenly lasts for months instead of hours.
- gambiting 13y agoAgain, a $20 multimeter wouldn't measure shit with a draw that small. And there are devices which use GSM radios for communication and last half a year on a 9V battery, for remote monitoring stations and such. So a virus implanted in a bootloader could very easily keep everything off and stay ready to spy. Your inability to accept this as a technical possibility is very childish.
- tghw 13y agoAre you sure it's off?
- Bosence 13y agoWould taking the battery out simply suffice, too?
- _fs 13y agoLooks like someone didn't RTA
- joelrunyon 13y agoThey address this at the bottom of the article (read the whole thing). Battery removal can be equally deceptive. Even once one figures out how to extract the primary battery, there may be additional power sources within the apparatus. “Some phones use an additional battery for memory management; it’s unclear whether this battery could be used by logging and/or tracking systems such as Carrier IQ,” Mr. Harvey explained, referring to software that monitors mobile phone users.
- kllrnohj 13y agoWhich is stupid because of how obviously wrong it is. Batteries that can sustain the cell radio, CPU, and audio DSP are not small and easily concealed, and more importantly tear downs of phones happen all the time and no such reserve power is ever found.
- kalleboo 13y agoA greeting card can make audio recordings. The upload could be postponed until later when the main battery is reinserted. (not saying that I believe that there's any way these phones are recording when the battery is removed, just that it is doable)
- kllrnohj 13y agoSure, but those greeting cards typically don't have quad core CPUs in them, either. You'd have to expand the claim to not only include hidden reserve power, but also hidden reserve memory, CPU, and audio system. Not to mention somehow convincing phone OEMs to actually spend the money adding this system to their motherboards and building it - there's no way in hell you are randomly sneaking that in at the factory without the OEMs knowledge. So now you also have to somehow keep the OEMs quiet about it. In a word, "bull-fucking-shit".
- kashnikov 13y agoAn anti-static bag should work just as well.
- CamperBob2 13y agoHard to imagine a worse Faraday cage than a refrigerator. The rubber seal would create a nice slot antenna running 3/4 of the way around one side. The microwave oven would be much, much better.
- jychang 13y agoThe rubber seal is a better audio seal though, which is more important.
- CamperBob2 13y agoProbably best to put the phones in the microwave, and leave the microwave in the bathroom with the shower running to create masking noise. Or just turn on the microwave for a few seconds. :)
- snogglethorpe 13y agoWrap the phones in tinfoil, put the wrapped phones inside the stainless-steel martini shaker (see other thread), put the martini shaker inside a microwave, put the microwave inside a refrigerator, and put the refrigerator in the bathtub. Now turn everything on "high", including the shower ("hot & steamy"), and run. Snowden's guests will have done that a while ago of course...
- tszyn 13y agoI just put my phone in the refrigerator and called it -- works perfectly. Then I tried the same thing with a microwave oven (following pilsetnieks's suggestions) -- didn't even lose one bar on the signal indicator. It did kill the Wi-Fi reception, so clearly the oven is blocking the 2.4 GHz frequency as it should. Edit: Also tried a cookie can. (And anti-static bags -- see below.) Faraday cage my ass. Clarification: I use a Nokia. Maybe the technique works only on iPhones? I've heard they have some reception issues.
- flog 13y agoGot an anti-static bag to try, as others suggested? Would be interested in your result.
- tszyn 13y agoTried two different types of anti-static bags -- even if I use two layers, the phone doesn't lose a single bar of signal strength.
- trotsky 13y agoI've recently tried the static bag using a samsung tablet - wifi and bluetooth both showed no attenuation with two different bags. A "farraday cloth" that was suggested to me is priced at about $24 a linear foot (8'x1') so I wouldn't expect these cheaper solutions to be very effective. I would expect a microwave oven cavity to effectively reduce signals in 2.4ghz, though not signals in the lower gsm and related bands.
- cyanoacry 13y agoAn anti-static bag (even the metallized type) probably won't be the best idea. Faraday cages depend on the conductivity of the outer shield to exclude electric fields from the inside, but anti-static bags aren't very conductive (100k-10G ohm square resistivity[1]). You might even be better off wrapping the phone in aluminium foil, but the problem is then going to be ensuring that all seams in the "cage" are actually conductive. [1]http://www.esdjournal.com/techpapr/ryne/esdbags.htm http://www.esdjournal.com/techpapr/ryne/esdbags.htm
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- flog 13y agoSo given that Snowden would be in the know about such things, this would confirm the legend of phones being remotely controlled for listening devices. Were there any iPhones in the fridge?
- rit 13y agoWhy would it confirm it? "Correlation does not imply causation". He may be pulled in by the same rumours as everyone else and being overly cautious. Just because he does this doesn't indicate he has confirmed or denied the existence of a slave microphone bug. Just that he believes strongly enough in the possibility to be cautious.
- Jach 13y agoCorrelation may not boolean-logically imply causation, but it's evidence of causation. http://oyhus.no/CorrelationAndCausation.html http://oyhus.no/CorrelationAndCausation.html The actual cases I've seen (some linked on this page) are of specifically targeted individuals having their phone receive a command to turn into a bugged phone. I don't think all phones are bugged by default. This fits with Snowden wanting people around him to sound-proof their phones as they might be targeted.
- atdepth 13y agoHow is this a legend? Didn't the FBI admit in at least two cases that this was the very technique they used to gather intel on the suspects?
- alan_cx 13y agoThis is absolutely NOT a piece designed to make Snowden look slightly odd.
- achughes 13y agoActually I thought the article put him in a better light than most of the other pieces about him. It makes him out to be more in tune with the ways the gov could track him. If they wanted to smear him then NYT could just come out with a short piece saying "Snowden made his Lawyers put their Phones in the Fridge", and then just spend the rest of the article speculating about his growing paranoia and questioning the decision. Instead they explained the logic behind the seemingly unreasonable request. How is that being malicious?
- crdoconnor 13y agoI think the fact that they're actually out to get him should dispel the notion that he's paranoid.
- alan_cx 13y agoI'm from the UK. We have tabloids. They will take a fact like (made up example) Snowden wanted all phones turned off, and simply make up the rest. 1) to demonize the subject, and 2) to put a more sexy sounding story in the paper. So, my natural default is to hope to believe the simplest "fact" in the story, if that. Maybe you have faith in your newspapers, and to be totally honest I don't actually know how Americans feel about their news papers. But you do have Murdoch floating around, so Americans are being manipulated somewhere. But I sure as hell dont take them at their word. For me, newspapers are as accurate as "the internet". But to me, that read like a slightly more sophisticated that a UK tabloid smear job. I do how ever accept that my UK perspective on the press might well be very different to a US one.
- swamp40 13y agoSomeone once came to us and asked us to design a wireless thermometer for a freezer. We told them it wouldn't work, because the freezer would act like a Faraday cage. Then they showed us a similar device that worked just fine. Embarrassing. We test a production device here that makes a LOT of noise, and we put it inside a mini-fridge to dampen the noise so it doesn't drive the testers crazy. Works quite well. I doubt you'd pick up any outside conversation if you were trying to eavesdrop (especially if the freezer was humming).
- planetjones 13y agoCouldn't he have just put the phones in airsafe mode? Plus if they were tracking the lawyers then they'd probably have seen them arriving at the location even if the signals went off when they arrived.
- keerthiko 13y agoIsn't just wrapping the phone in aluminium foil (as many layers as needed to make you feel comfortable) enough to act as a faraday cage? And leaves the cellphone still portable, you can unwrap if/when needed. And then bury it in a pile of clothes in another room (as the article suggests somewhere) for the soundproofing. The refrigerator I feel serves neither of these purposes well (as mentioned in this discussion), and ruins everything when it's time to make a sandwich.
- mahyarm 13y agoAluminium foil does shit all, I've tried it before trying test a signal loss case where I work. It can be kind of tricky to do this stuff actually, the martini shaker one is actually something I'll be using.
- pronoiac 13y agoIt has to be grounded to properly act as a Faraday cage, doesn't it?
- gweinberg 13y agoI just tested this, aluminum foil does seem to block signals coming to my phone. At least, the wrapped cell phone doesn't ring when I call it with my house phone. The wifi signals may still be getting through, I don't know.
- betterunix 13y agoMy initial reaction was that the phones-in-the-fridge rule was meant to muffle sounds. Can anyone comment on whether or not a phone in a fridge can pick up sounds from the room the fridge is in?
- cheald 13y agoSeems like the kind of thing that you could test empirically.
- rayiner 13y agoSlightly tangential story. My first assignment on my first job was building a knockoff TEMPEST enclosure (http://www.jammed.com/~jwa/tempest.html http://www.jammed.com/~jwa/tempest.html) to isolate spectrum measurement equipment. The original use of the enclosures was (somewhat ironically given the article) the NSA's paranoia that foreign intelligence would spy on government computers by picking up their EM radiation. So if you're worried about the government spying on your computers via RF and want something more convenient than a fridge, drop me a line...
- MWil 13y agoif you're feeling like a profiteer why don't you just start selling a faraday cage phone case
- frozenport 13y agoPhone won't work inside the case?
- MWil 13y agoexactly. the slogan is "It's a phone when you want it, not a bug when you don't!"
- at-fates-hands 13y agoVerizon uses an 700MHZ and 1700/2100MHZ signal on their 4G network which will give you incredible penetration. People brag about how you can be in a basement of an office building (lots more concrete and steel than a refrigerator) and still get great reception. http://en.wikipedia.org/wiki/Verizon_Wireless#Radio_Frequency_Summary http://en.wikipedia.org/wiki/Verizon_Wireless#Radio_Frequenc... If they were using a carrier in Hong Kong, most of the carriers use a higher spectrum, usually around the 1800-2100MHZ range. While it doesn't give you great penetration in buildings like the lower frequencies Verizon use, I'm guessing the overall density of the towers is significant which would help this issue. If he said they want into the basement of a building THEN put the phones in the refrigerator, it would be a little more believable. Just putting it in the refrigerator probably won't do a lot to block the signal.
- deleted 13y ago[deleted]
- rayiner 13y agoIts not the mass of concrete and steel, but the faraday cage effect of a continuous closed loop of conductive material. Though aas has been pointed out, a fridge probably isn't electrically continuous at the door gasket. Depending on the construction, you could replace the rubber gasket witha rubber core metal mesh gasket.
- EGreg 13y agoI am pretty sure that if someone wanted to they could easily construct a faraday cage, instead of using a fridge! http://www.disaster-survival-resources.com/faraday-cage.html http://www.disaster-survival-resources.com/faraday-cage.html By the way, it's also useful against solar flares...
- rayiner 13y agoIf you want something NSA scale, you can do better than that. I used to use Copper-Beryllium mesh and gaskets (http://www.sealingdevices.com/metal-emi-gaskets-and-becu-beryllium-copper-springfingers http://www.sealingdevices.com/metal-emi-gaskets-and-becu-ber...). Choose mesh size based on the frequencies you expect to deal with (and harmonics). If you want to keep your computer in there you also have to be careful designing the ports for wires coming in/out.
- EGreg 13y agoWhy do you say that about the ports?
- kefka 13y agoEvery wire is also an antenna that is attenuated to the appropriate frequencies related to the length of the wire. A 2 meter cable also receives on 144 MHz any spurious signals (amateur radio band). If that was an EMP, it would send a voltage spike up the port and blow out whatever it hit.
- EGreg 13y agoOh, I thought you meant that the faraday cage would interfere with the wires conducting electrical signals
- DanielBMarkham 13y agoYeah, that's not going to work as a Faraday Cage. I guess you'd have to put the cellphone in the microwave, then put the microwave in the refrigerator. That's going to look weird. :) I used to do a bunch of micro-sites -- small websites targeted around specific topics. One I did a few years back was http://gps-cell-phone-tracking.net/ http://gps-cell-phone-tracking.net/ I really learned a lot setting that site up, and it was one of the reasons I became such a privacy freak. Our cell phones are basically tracking devices the government monitors which we happily adorn to our bodies each day. Weird. To get to my point, one of the questions on the site was whether your phone could be tracked, either location or having the audio monitored, without your knowing it. Location is easy -- yes. Audio was a bit weirder. Obviously you'd have to install an app, and who would want to do that? Then I learned that cell providers will "help" governments by putting tracking code inside the auto-update of the phone. They can even push it at night and have it install without your having any knowledge at all. As far as I know, pulling the battery still kills things, but then somebody said most phones have a dual battery to keep the memory refreshed. Somebody even said something about the possibility of "illuminating" phones from a distance and picking up audio that way. Of course, "somebody said" doesn't count for much, and with all the secrecy in place good luck figuring out what is what. Fun stuff. Since the micro-site business didn't take off, maybe there's a future in selling tin-foil hats?
- kintamanimatt 13y agoI hope the fridge was off. A fridge will act as a fantastic acoustic shield but probably not a functioning Faraday cage. I think this blog post has taken a few artistic liberties in suggesting its use was as a Faraday cage, especially as the article she links to doesn't mention the fridge's purpose as a Faraday cage. Assuming this story isn't stretched and exaggerated (I have a hard time believing it isn't) and the fridge was on, this could be a fast way to trigger condensation to form inside the phone when the device is removed back into a warmer environment, depending on the ambient humidity. I just wouldn't dream of putting my phone in a cold fridge for anything other than the briefest time for this reason.
- jevinskie 13y agoWhy not on? Wouldn't the compressor improve the situation by adding background noise? Also if condensation is a concern you can put the phones in a plastic bag.
- kintamanimatt 13y agoWhen a fridge is on it usually means it's cold! If it's off (and has been for a while) it could be expected to be around room temperature, eliminating the issue of condensation. The compressor isn't on all the time. It turns on intermittently when the temperature inside the fridge exceeds a certain threshold. It would be unlikely of much use most of the time. Putting the phones in a bag does nothing to solve the issue of condensation. What happens is the phones would cool down substantially in the fridge. When they're removed, the cold surfaces (inside and out) would cause moisture in the warmer air to condense into water droplets, possibly causing issues with the battery and the other circuitry. Hong Kong is quite a humid place and it appears that he was at an acquaintance's home at the time of the frigid phone incident. It's unclear how well air conditioned this acquaintance's home was, which could lead to some especially nasty condensation issues. It's also unlikely this acquaintance's fridge would have been brought up to room temperature just for the sole purpose of storing phones for a couple of hours. This is why I'm inclined to believe the anecdote is BS.
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- Snowda 13y agoI bought some EM radiation blocking cloth from LessEMF and stitched it to the inside pocket of my jacket which I rarely use. If I'm feeling paranoid (or if I'm not arsed to turn on airplane mode to save battery) I just put it in that pocket instead of the normal one and zero communications can get in (especially my mother)
- GoodIntentions 13y agocurious. Do you notice decreased battery life if you do this? I would think you would chew through battery like a mofo if you block carrier, but leave the phone on. It's gonna try hard to hit a tower non-stop, I expect.
- crdoconnor 13y agoMy phone does. If I ever take it to an area with zero reception and forget to turn on airplane mode, the battery dies in 2-3 hours.
- leke 13y agoI used to work as a phone tester and sometimes had to test things while the phone was in a unreceivable location. I tried many things, like a safe, fridge, cookie jar etc, but the only thing that worked was wrapping the phone in 2 or 3 layers of tin foil.
- hawkharris 13y agoI usually tell the lawyers to put the phones in their a--. It's not more effective, per se, but it's certainly funnier.
- hawkharris 13y agoOkay, I admit that I deserve a downvote for this...But I couldn't resist :)
- aplusbi 13y agoI used to develop nintendo DS games and once received a very memorable bug report - something to the effect of "got error [error message] when playing the game in a microwave". We weren't handling lost wifi connections gracefully so the user would get the wrong error message if their wifi dropped. The tester was simulating this by placing the DS in a microwave.
- doctorstupid 13y agoObama has his own Faraday tent: http://www.bbc.co.uk/news/world-us-canada-12810675 http://www.bbc.co.uk/news/world-us-canada-12810675
- gojomo 13y agoWe need to crank our paranoic creativity up to 11, people. The fridge itself had a false back. Snowden's associates in SPECTRE/Wikileaks then used their covert physical access to the phones, for the duration of the dinner, to copy the phones' contents and install new malware. Now, they know what the lawyers know -- including whether any are double/triple/etc-agents.
- reeses 13y agoJeez, I missed this when I posted my reply. It looks as if we're the only two paranoid enough to see the danger and stupid enough to point it out and draw attention to ourselves. I'm sleeping in the bunker tonight.
- jstalin 13y agoI just tried putting my cellphone in a stainless steel martini shaker and it definitely worked as a faraday cage.
- e12e 13y agoThat's some real James Bond shit, right there! (sorry, couldn't resist :)
- quackerhacker 13y agoI won't speculate on eavesdropping since I haven't tested this, but what I hear when I heard his method is more of the security risk that he could possibly be pinpointed. A red flag would go up for me, hearing multiple people (the lawyers) clustering to one location. Smartphones are a beacon of constant info...GPS and signal pinging can get your coordinates (at least general area), and Wifi can triangulate the position [0]. Cameras and microphones are just icing and still require a device to be compromised, whereas signals, require carrier network access...which is what PRISM revealed [1]. [0] http://thenextweb.com/apple/2013/03/26/what-exactly-wifislam-is-and-why-apple-acquired-it/ http://thenextweb.com/apple/2013/03/26/what-exactly-wifislam... [1] http://news.cnet.com/8301-1009_3-57589100-83/nsa-whistleblower-u.s-has-been-hacking-into-china-hong-kong/ http://news.cnet.com/8301-1009_3-57589100-83/nsa-whistleblow...
- chrsstrm 13y agoYou would think instead of stashing them in the fridge, he would ask visitors to not carry a GPS receiver right into his hideout. We complain about the gov possibly bugging and tracking us, yet we do it to ourselves willfully almost 24/7.
- hawkharris 13y agoComments on this story illustrate the difference between Hacker News and other news sites. Most people say "That's cool" or maybe share links related to the research. People on HN said, "Okay, now that all our phones are locked in the freezer, let's compare data." :)
- semiprivate 13y agoThe real answer: he looked around the house and decided it was the best place. lots of metal, and a hum to drown out noise. The NSA leak was important enough, we don't need to pretend like he's some kind of privacy McGuyver.