🔗 Van Eck Phreaking

🔗 Espionage 🔗 Internet 🔗 Telecommunications 🔗 Computer Security 🔗 Computer Security/Computing

Van Eck phreaking (also known as Van Eck Radiation) is a form of eavesdropping in which special equipment is used to pick up side-band electromagnetic emissions from electronic devices that correlate to hidden signals or data for the purpose of recreating these signals or data in order to spy on the electronic device. Side-band electromagnetic radiation emissions are present in (and with the proper equipment, can be captured from) keyboards, computer displays, printers, and other electronic devices.

In 1985, Wim van Eck published the first unclassified technical analysis of the security risks of emanations from computer monitors. This paper caused some consternation in the security community, which had previously believed that such monitoring was a highly sophisticated attack available only to governments; van Eck successfully eavesdropped on a real system, at a range of hundreds of metres, using just $15 worth of equipment plus a television set.

As a consequence of this research, such emanations are sometimes called "van Eck radiation", and the eavesdropping technique van Eck phreaking. Government researchers were already aware of the danger, as Bell Labs had noted this vulnerability to secure teleprinter communications during World War II and was able to produce 75% of the plaintext being processed in a secure facility from a distance of 80 feet (24 metres). Additionally the NSA published Tempest Fundamentals, NSA-82-89, NACSIM 5000, National Security Agency (Classified) on February 1, 1982. In addition, the van Eck technique was successfully demonstrated to non-TEMPEST personnel in Korea during the Korean War in the 1950s.

While Phreaking is the process of exploiting telephone networks, it is used here because of its connection to eavesdropping. Van Eck phreaking of CRT displays is the process of eavesdropping on the contents of a CRT by detecting its electromagnetic emissions.