From the AEGIS e-Journal, Volume 2 Number 11, November 1999
According to a California engineer who demonstrated a home-brew computer death-ray, with $500 and a trip to the hardware store saboteurs can build a device capable of remotely disrupting computers, automobiles, medical equipment, and nearly anything else dependent on electronics. The engineer showed off an unwieldy device constructed from a parabolic reflector, a horn antenna, and two automotive ignition coils, which he aimed at two personal computers about 20 feet away. When an assistant activated the device by connecting it to a car battery, the room filled with a loud buzzing from the PA system and a Power Point presentation on one of the computers flickered and scattered. The other computer instantly dropped out of its screen saver. When the device was switched off, both PCs were frozen, and wouldn’t respond to keyboard input. The effects of High Energy Radio Frequency (HERF) emissions on electronics are well known among engineers, and info-warriors have expressed concern that adversarial nations may someday include computer- killing devices in their arsenals. But small-scale electronic warfare is possible, and even low-budget saboteurs can create viable electronic weapons. The HERF gun is not particularly high-tech. The device uses technology dating back to Tesla, essentially pushing a 20-megawatt burst of undisciplined radio noise through an antenna. The energy is enough to interfere with sensitive computer components nearby, creating unpredictable results ranging from minor anomalous behavior to complete burnout. Larger HERF guns are capable of crashing computers and disabling automobiles at a range of 100 feet, with a cost as low as $300. The computers targeted in the demonstration worked fine after rebooting, and permanent damage is uncommon. “But if that happens to be a computer in a tank, or in a piece of medical equipment, how long does it take to reboot?… By that time you could be dead.” HERF gunning is outside the scope of firewalling but it is an issue to be addressed as a real concern, and a HERF attack might be regarded as a variation in ‘denial of service attacks,’ as are attacks on firewalls, as well as many computer viruses. The question of whether HERF guns exist (they do) and, if so, whether they work (they work) is less important in some respects than the fact that several incidents have involved claims by extortionists that convinced the victims to part with money. ÆGIS, November 1999 7 What is still conjecture is how many victims have been hit and how much they paid for ‘protection.’ At least one police force would like to know the answers in their area of jurisdiction. As with many incidents of extortion, victims are very reluctant to admit that they have been targeted or that they have paid. One reason for that is that they don’t want to look vulnerable and stupid. Another good reason is that they don’t want to encourage further attacks.