A team of researchers from Israel has developed a piece of malware that demonstrates how hackers can abuse security cameras with infrared (IR) capabilities to send and receive data to and from an air-gapped network.
The research was conducted by the Ben-Gurion University of Negev and the Shamoon College of Engineering in Israel. Its goal was to show that a piece of malware installed in an air-gapped network can not only exfiltrate sensitive data, such as passwords, PINs and encryption keys, but also receive commands from the outside world via infrared light, which is invisible to the human eye.
Security cameras are typically equipped with IR LEDs that provide night vision capabilities. If an attacker can plant a piece of malware on the network connected to these cameras, the malware can take control of the IR LEDs and use them to transmit bits of data.
The malware described by experts, dubbed “aIR-Jumper,” can encode the stolen data using various methods. For example, if on-off keying (OOK) encoding is used, the absence of an IR signal for a certain duration encodes a zero (“0”) bit, while the presence of a signal for the same duration encodes a one (“1”) bit.
Encoding one character of a password, PIN or encryption key requires 8 bits (1 byte). However, for data transmission purposes, the researchers suggested also adding preamble bits for calibrating certain parameters (e.g. LED location and IR levels) and synchronization with the beginning of the transmission, and some bits for error detection.
Another encoding method suggested by the researchers involves frequency changes. For example, a “1” is encoded if the LED is on for a certain duration at a certain frequency, and a zero is encoded if it’s on at a different frequency. Similarly, intensity level changes, or amplitude shift keying (ASK), can be used.
Data transmission rates depend on the security camera and the camera used to capture the data (e.g. GoPro, smartphone camera). Experiments conducted by the researchers showed that data can be exfiltrated at a rate of 20 bits/sec over a distance of tens of meters, and it can be infiltrated over a distance of hundreds of meters and even kilometers at a rate of 100 bits/sec.
Data transmission rates can be increased significantly if more than one security camera is used by the attacker. Videos have been published to show how the infiltration and exfiltration attacks work:
Ben-Gurion researchers have dedicated a lot of their time to finding ways to exfiltrate and infiltrate data on air-gapped networks. Their previous work involved using router LEDs, scanners, HDD activity LEDs, USB devices, the noise emitted by hard drives and fans, and heat emissions.
