In the Blink of an LED, Secrets Slip Away: The Rise of Optical Data Theft

Air-gapped systems which are physically isolated from external networks have been the last line of defense for high-security environments. But in 2025, even isolation isn't enough. Why? Because attackers have learned to blink the data out.

For decades, air-gapped systems which are physically isolated from external networks have been the last line of defense for high-security environments: nuclear facilities, defense networks, R&D labs, and critical infrastructure. But in 2025, even isolation isn't enough. Why? Because attackers have learned to blink the data out.

Welcome to the covert world of optical data exfiltration, where malware manipulates LEDs, Morse code becomes a medium, and surveillance cameras act as listening posts.

Leaking Data with Light

The technique is deceptively simple, yet incredibly effective.

1. A compromised air-gapped system is infected with specialized malware via insider access, compromised USB, or supply chain infiltration.

   
   

2. The malware encodes sensitive data ...