Researchers Hack Air-Gapped Computer with Simple Cell Phone

'The attack requires both the targeted computer and the mobile phone to have malware installed on them, but once this is done the attack exploits the natural capabilities of each device to exfiltrate data.'

So it needs a previous security breach. Challenging, because as the article mentions, in secure environments the pc is not connected to internet nor are USB sticks allowed.

> It works with simple feature phones that often are allowed into sensitive environments where smartphone are not, because they have only voice and text-messaging capabilities and presumably can’t be turned into listening devices by spies.

I have no idea where they got this information from, because it is absolutely false in DOD classified environments. Anything that can be used as a recording device or that can transmit information wirelessly is restricted or prohibited, and personally-owned examples are strictly prohibited. In very strict environments, even receive-only electronics may be restricted.

I am not personally aware of any policy that makes a distinction between "smartphones" and "feature phones". The only thing I have ever seen referenced is phones with cameras, and even that was only for visitors in the unclassified areas.

If someone installed malware on that computer already, all bets are off. It might as well be a radio transmitter that's broadcasting every keystroke. The title is sensationalistic, because the hard part was installing malware. The "simple cellphone" part is meaningless.

Won't the modulating/transmitting malware increase the system cpu load (run queue, or whatever)? This could be a detection vector for it.

I have noticed when running a program that does nothing but work the memory bus, Memtest86+, the computer gets hot and draws a lot of power.

1. That connector size appears to be a DVI connector. How does TMDS affect data transmission via TEMPEST leakage?

2a. Would HDMI render this attack void, due to encryption on the data signal layer?

2b. Since the HDMI master keys are known, would it be possible to modify data with the now-known key and pass data using this method?

3. What card is shown on the desktop? That looks like a rather suspicious card (GSM card?).

My desktop is in a metal case. Shouldn't that block any RF leaking out of it?

If the attacker has installed malware on the target machine and has physical access to it, literally nothing will save you.