“Security cameras are unique in that they have ‘one leg’ inside the organization, connected to the internal networks for security purposes, and ‘the other leg’ outside the organization, aimed specifically at nearby public space, providing very convenient optical access from various directions and angles,” Mordechai Guri, head of research and development at Ben-Gurion’s cyber-security research center, told Ars.
Hidden communication via security cameras.
Leaking data via security cameras.
aIR-Jumper uses several different schemes to encode the zeroes and ones that form the basic building blocks of all digital data. The malware breaks large data streams into small packets or frames that include a preamble, a payload, and a 16-bit cyclic redundancy check to ensure the data was sent correctly. The proof-of-concept attack uses an infected camera’s own programming interfaces to control the infrared LEDs to transmit the data according to the encoding scheme and other parameters selected. Infrared LEDs are used to enable night vision so that cameras can produce images when there is little or no ambient light.
aIR-Jumper works best when attackers have direct line of sight to the video camera inside the infected network. Non-line-of-sight communication is also possible when the area illuminated by infrared lights is within the field of vision of the receiver. The attack is not only useful for air-gapped networks. It is also suitable for internal networks where traffic is heavily monitored by firewalls, intrusion prevention systems, and similar security measures, since it can bypass them without requiring any physical access between the attacker and the network.
aIR-Jumper is only the latest covert channel devised to shuttle data into and out of air-gapped networks once they have been infected. Previous proof-of-concept attacks developed by many of the same researchers include the manipulation of acoustic signals emitted from hard drives, malware that turns USB devices inside an air-gapped facility into covert radios that transmit data through electromagnetic signals, and a technique that allows an infected computer’s video card to transmit radio signals that can be received by a smart phone.
The wide body of attacks starts with the assumption the attacker has already infected the target with malware. The research shows that air-gaps alone aren’t always sufficient for ensuring an attacker can’t transfer data into and out of mission-critical networks. Countermeasures against the aIR-Jumper include placing surveillance cameras in restricted zones that are optically inaccessible to attackers.