At 11:42 pm, Britt's eyes snapped open. She shot up in bed, wide awake, heart pounding. Sirens screamed. Her neighbors hollered and scrambled around the courtyard of her modern Dallas apartment complex. The Midwest native is accustomed to hearing storm sirens. The Dallas sirens were different. And louder. The blaring monotone warning radiated from every direction.

This article originally appeared on ZDNet's sister site, TechRepublic.

"In a tornado, the siren will shut off when the storm passes. These were much louder and blasted for a long time. We had no idea what was going on, but we knew it wasn't a tornado. There was a guy standing close to my window screaming, 'We're at war! The shit's going down!'" For a fleeting moment, she said, "I thought he might be right."

On April 7, 2017, a radio frequency trigger hack caused 156 emergency sirens in Dallas, a city of 1.2 million people, to wail concurrently for 81 minutes. The incident serves as a clarion call to organizations everywhere that cyberweapons could be used against your infrastructure in order to make a statement.

"Technically, each siren went off for 90 seconds, 15 times. There was a lot of confusion," said Dallas public information officer Richard Hill, because there were no storms in the region. "We had close to 4,000 calls to 911. The system was nearly overwhelmed."

The Dallas siren episode will be increasingly common, and enterprises and public organizations are targets. CIOs will have to adapt to an increasingly volatile security landscape driven by new Internet of Things (IoT) threats, malware, and artificial intelligence. Consider: A ransomware attack that hit the UK's National Health Service (NHS) brought down hospital systems initially, then went global. 

As a show-of-force in December 2015, cyberattacks by Russian-linked hackers took down a large portion of the Ukraine power grid. "The initial breach of the Ukraine power grid was--as so often in cyberattacks--down to the human factor," wrote ZDNet's Charles McLellan. "Spearphishing and social engineering were used to gain entry to the network. Once inside, the attackers exploited the fact that operational systems--the ones that controlled the power grid--were connected to regular IT systems."