Grand Idea Studio

Optical Covert Channels


Data exfiltration from a compromised device is usually achieved over the network, via hardware implant, or by manipulating the characteristics of an internal electronic component. Optical covert channels transmit data by modulating visible light in a way that is undetectable to the human eye.

The OpticSpy modules provide a platform to explore, evaluate, and experiment with optical covert channels. They capture, amplify, and convert an optical signal into digital form that can be analyzed or decoded with a computer.

The Crowd Supply edition of OpticSpy is available for purchase here.

All designs are distributed under a Creative Commons Attribution-3.0 United States license.



OpticSpy Digital:

OpticSpy Analog:

OpticSpy Analog (Crowd Supply):



Using an Arduino Uno with external LED to send a secret message via optical covert channel.

Parallax Propeller:

Using the Propeller-based Hackable Electronic Badge to send a secret message via infrared LED. The LCD displays the message being transmitted.


Using Tomu’s red LED to send a secret message via optical covert channel.

TP-link TL-WR841N:

Using the router’s WAN LED to exfiltrate data via optical covert channel. As a proof-of-concept, the payload is loaded onto the device with known administrator credentials.


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