Bitcoin Forum

http://www.bloomberg.com/news/2014-11-19/hackers-can-steal-data-wirelessly-from-pcs-that-aren-t-even-online.html

This is something to be aware of when doing cold storage.

The gold standard of "use a machine that has never been connected to the internet and never will be"
will protect against this unless someone has physical access to the computer...
but are there other ways to also disable graphics card to prevent the attack described here?

You realize that only works if someone has PHYSICAL access to the device with the cold storage? With physical access, it's easier for a thief to steal the wallet file, regardless if it had internet or not.

Cracking the password to the wallet is another story.

It's why using a USB stick to ferry data/transactions between your hot and cold machines is really a breach of the air-gap. Any transfer of data is. (And presumably if your hot machine is infected, any virus can just pass data back via the USB stick, it doesn't need any fancy radio transmissions.)

All input/output needs to be considered a potential conduit for viruses...

The ideal cold wallet wouldn't rely on any data from the outside world. I'm not sure that's possible though. Maybe by splitting the balance into many small amounts on separate private keys and just removing a single private key for a small amount at a time. So the data transfer is only ever *from* the cold machine to the hot machine, via paper wallet or photographing a QR code or something.

I'm wondering whether laptops qualify as having a "display cable".



Agreed, but:



Does this include the following?

- Reading some words/digits in the online computer.
- Walking to the airgapped one.
- Manually typing the memorized words/digits on the keyboard.

It's effectively a data transfer but the bad guys would have a really hard time trying to compromise the airgap through it. Of course it's inconvenient as hell but we all know that's the price you pay for security :).

The only safe machine for cold storage is an Altair, where you hand toggle the wallet program and keys in on the front panel.  :P

And never use a VDU with it, makes it harder to Van Eck.

And always do 3 pulses with a flashgun into each eye before you leave the secure area, just in case retina forensics can recover recently seen things.

That and your brain. A key to an address is just information after all.

And practise thinking in an unspoken language, now that brain scans can infer thoughts from nerve activity required to talk.

Ouch. Could you give some reference to this?

http://www.newscientist.com/article/mg22429934.000?cmpid=NLC

I guess you might get away with that... ;)

But I don't think the risk is quite zero. Probably minuscule enough though.

This hack needs a virus, a receiver/transmitter near the video cable and a phone to download. If a hacker has so much access to the target machine, it is easier for him to actually steal the data when he plugs the usb drive in the computer.

I was expecting something like the "wirelessly steal data device" from Prison Break season 4 :D

Right. If a hacker had physical access then they might as well make a copy of the hard drive and/or outright steal your computer in an attempt to steal your wallet files. This would make more sense then going through the hassle of taking data wirelessly as I would imagine that many people would tend to have somewhat easy to crack passwords on computers that hold cold storage wallets

Anyone here want to buy a tin-foil hat? Made to measure. I accept bit-coin.

The article didn't say what kind of graphics card and cable would be most susceptible to being used as an FM transmitter to leak the data - VGA, DVI, HDMI, RGB? I am willing to bet that it only works reasonably well on one of these types of cables, and not so well on the others. So find out which one and use that cable. It would also be reasonable to assume that using a laptop computer or some other type of computing device that does not have a long video cable would greatly mitigate this kind of attack.

Together with the entire computer were stolen?
Aha that's not a hacker, called a thief  ::)

Physical access is not required in many cases.  Since 2009 (32nm Sandybridge) all Intel CPUs have vPro AMT built in, allowing anyone to control the computer remotely using wireless 3G technology.  There are remote exploits in the wild and the technology cannot be disabled by the end user, the setting to disable AMT in the Bios is ignored.

"Currently, Intel AMT is available in desktops, servers, ultrabooks, tablets, and laptops with Intel Core vPro processor family, including Intel Core i3, i5, i7, and Intel Xeon processor E3-1200 product family"
http://en.wikipedia.org/wiki/Intel_Active_Management_Technology

"AMT is designed to help sys-admins remotely manage and secure PCs out-of-band when PC power is off"
http://en.wikipedia.org/wiki/Intel_AMT_versions

Keywords are "out-of-band" and "when PC power is off".  The Intel CPUs are always on, even when they are off, provided the computer is plugged in to the power.  They can remotely access all your data anytime they wish, without permission and without anyway for the end user to disable this "feature".  It is well documented, so there should be no surprises here.

So, just plug it off, when you don't need it?
Doesn't sound that complicated to me ...

Btw. my computer is always unplugged, when I switch it off, since i just hit the button on my multi-plug.

From my brief reading, it does require a 3G card of some kind. So as long as you remove any such thing from your offline machine you should be OK. But it's still scary of course.

I would be interesting in seeing any links to actual exploits/demonstrations. There seem to be a lot of FUD articles on that topic and not many actual facts.

Completely useless article and un-related. How exactly would one be able to get this virus into a machine i.e. cold storage?
If my damn PC is in my attic, have fun making it's GPU transmit signals.  :D
Have fun siphoning data from an encrypted drive  ???

Also:

This is scary stuff. If the power and network cable is plugged in and the cpu can connect to the internet and ping another ip, giving the location away. It can't access any data on harddisk though.

another way into your pc is through your wireless usb's like you would use for your keyboard and mouse.

same thing with your ip television. you can have ur tv turned off but the tv is still getting power and can still be used by NSA hackers to monitor you eating your bowl of #ebolas in the morning..
to circumvent this problem i use a voltage regulator between the wall outlet and the surge protector and cut the voltage regulator power when tv is not in use.
the voltage regulator will save you from coming home and finding your tv doesnt work anymore because of dirty power as well .
you should disconnect your internet modem when not in use (keeps hacker neighbors from getting used to stealing your bandwidth).
and only use hard wires in your home network disabling the wireless in your router until needed.

Completely agree. Sad part is this FUD probably scared some people.

Well that's why FUD spreaders do their work.
If we were to go in further and analyze this in details, we would find much wrong with the allegations. Same thing with that USB bug. Taking into consideration the number of USB devices, people that could implement the virus and the amount of devices that have been actually 'modified' the chances of you getting infected are almost impossible. Yet that scared people of this community.
The Intel AMT feature can't be on and set up by default. That would be a major flaw, and would have been discussed long ago.

There is a small battery in the CPU (? - I believe this is where it is) that keeps power so the BOIS settings can be 'remembered'

In reality the simplest solution would be to line the inside of your computer with tinfoil. This would prevent an attacker from being able to receive any signal your computer is transmitting, as well as to prevent you from looking crazy. 

Not in the CPU, it's a separate component on the motherboard.

Lining the case will not help if it is the cable to your monitor that is leaking the RF. So you would have to wrap the foil around that cable, and earth it.

Or you could put another, very noisy, RF setup in the same room.

Finally, a use for my BFL Singles :D

I don't think it has been shown that monitor cables are able to leak this kind of information as described in the OP. I also don't think it would be all that difficult to line your monitor cables (and mouse/keyboard cables if you want to get similarly paranoid) to protect yourself against this kind of attack

My thoughts exactly. The odds of something like this happening to the one computer out of 1 million that actually has significant Bitcoin on cold storage is greater than being run over by a truck and then by a motorcycle and still living.

If you're really that nervous, save each Bitcoin in a different brain wallet and memorize each different one. See how that works out for ya.

BTC https://www.igot.com/?inviter_code=1014280323 BTC save it on igot. ;D

"Intel actually embedded the 3G radio chip in order to enable its Anti Theft 3.0 technology. And since that technology is found on every Core i3/i5/i7 CPU after Sandy Bridge, that means a lot of CPUs, not just new vPro"
http://www.infowars.com/91497/

The CPU itself is a 3G transmitter/receiver.  The CPU contains a separate computer inside, with it's own memory and storage, it operates at Ring -2 and beyond which is below the operating system at Ring 0, it is also below a hypervisor at Ring -1.  It cannot be detected by the operating system and it is standalone.


It can access the hard disk drive and any storage devices plugged into the computer, that is it's intended purpose, to be able to switch the computer on remotely and make changes to the operating system and hard disk drive.


Yeah this is complete lie, it is enabled by default and cannot ever be disabled, configuration is not necessary.

"Intel AMT backdoor enabled by default"
https://forums.lenovo.com/t5/Security-Malware/Intel-AMT-backdoor-enabled-by-default/td-p/824749

"Yes, but our rootkit would still be active. We have determined that some AMT code is still being executed, regardless of whether AMT is disabled in BIOS or not. In our proof of concept rootkit we decided to subvert this very AMT code."


Many exploits exist using various approaches, a demonstration was given at the Black Hat Conference in Las Vegas a long time ago in 2009.

"Invisible Things Lab's Rafal Wojtczuk and Alexander Tereshkin will present two new technical presentations at this year's Black Hat Conference in Las Vegas, NV, in July. The first presentation will talk about a new type of stealth malware, that potentially could be more powerful than kernel-mode, hypervisor-mode, and even SMM-based rootkits"
http://theinvisiblethings.blogspot.com/2009/08/vegas-toys-part-i-ring-3-tools.html

https://i.imgur.com/z5hCXWx.png

Here is the proof of concept code:
http://invisiblethingslab.com/resources/bh09usa/ring-minus-3-tools-1.3.tgz

It is concerning that you show an interest in 'how' it is done.

Yes, even those methods are not safe strictly speaking.  Theoretically a virus can trick you into recording the wrong data.  A truly safe cold storage device can only ever safely transmit data out of itself, never receive input data, as such input data can never truly be guaranteed to be secure.

This would make it impossible to even create cold storage in the first place. If cold storage can never receive input data then you would not be able to install anything that would create the private key or figure out the public key from the private key. It would also effectively make it impossible to ever spend any of your bitcoin in cold storage.

There are hardware cold storage devices available for sale now that never let the private key be known, they are able to sign messages to facilitate sending coins.  In other words, the private key is never used by any software on any internet connected computer or device, the cold storage wallet private key can remain in cold storage while allowing you to send coins.

I think, I was lucky, to get my hands on a old out dated computer on it's last legs!

I created hundreds of paper wallets, when I was offline and destroyed the whole computer afterwards. It is officially e-rubble now! {Small pieces, melted down}

If you have a old computer luying somewhere in a corner, and you are going to dispose of it, use it for a last time, and destroy it.  ;D ;D