Unsolved Cyber Mysteries: Signal Hacking

When people hear about a cyberattack, they think of sophisticated attacks carried out against complex systems by a shadowy cabal of miscreants out to cause damage, steal information, or make money. Back in 1987, there was a decidedly low-tech attack sprinkled with a “general spirit of anarchy that made it [the attack] all jaw-droppingly watchable.”

Episode 1 of Bugcrowd's "Unsolved Cyber Mysteries" describes a 1987 cyberattack affecting two Chicago TV networks. On the evening of Nov. 22, Chicago residents watching the 9 p.m. news (WGN) saw their TV screens suddenly go black for a few seconds. A person in a Max Headroom mask appeared on the screen. WGN engineers managed to take back control of the broadcast signal by changing the studio-to-transmitter frequency about half-a-minute later.

The same thing happened again two hours later, during an episode of Dr. Who, airing on a different channel (WTTW). This attack lasted about 1 minute and 22 seconds.

In this episode of the docuseries, Bugcrowd founder and CTO Casey Ellis discusses signal hacking and how this kind of attack does not require deep technical know-how of broadcast signals and technology or $25,000 worth of specialized equipment to carry out. Instead, it turns out that almost anyone can override local TV signals by pointing a transmitter at the transponders used by the stations and using a higher power.

"[The] signals had been hacked using analog and old-school techniques over the airwaves, whereas previous cases had used internal broadcast equipment that left digital fingerprints for investigators to find," Ellis said in the episode.

Signal hacking attempts back in the 1980s were "small, personal pranks on the system that ultimately did no harm to anything other than corporate egos," Ellis said, which is a far cry from modern cybercriminal groups using the Internet to make money.

“[The] buzz that surrounded the Chicago signal hacking is yet another example of how the methods, messages, and mayhem of hacking fascinate us all,” Ellis said.