SN-753 Data Exfiltration By Screen Brightness

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New member
Feb 9, 2022
Steve talks about an Israeli university group developing a technique to exfiltrate data from a system by undetectably varying the screen brightness to transmit data to a nearby camera.

Turns out I recall this handheld Wheel of Fortune game from 1988 which used this technique to transmit the broadcast game data to the handheld. It had several hundred puzzles programmed into it, you could play with VCR tapes they sold, and you could play along with the broadcast show.

During the show they would tell you when to point the sensor at the screen, and it would use light levels on the TV screen to transmit the data. It would indicate that the data was received and you played along with the contestants on the show.

Here's a review of the game:

And they're still available on ebay

It was just neat that when he mentioned this, I remembered this game from over 30 years ago.

Sorry about going so far back in time, but I listen to the podcast in the car on the way to work, and when I was working from home for a year and a half, I didn't use the car. So now that I'm driving to the office again, I'm binging to catch up. I got my notes together and created an account to post about stuff.
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