Today, WIRED is publishing the untold story of the most devastating cyberattack in history, which crippled the global supply chain and cost more than $10 billion in damages.

The attack took place one year ago, on June 27, 2017. In a matter of hours, a piece of malware called NotPetya laid waste to the computer systems of global companies including pharmaceutical giant Merck, delivery company FedEx, Nabisco and Cadbury parent company Mondelez, French construction company Saint-Gobain, British manufacturer Reckitt Benckiser, and shipping company Maersk.

Maersk alone is responsible for 76 ports, nearly 800 seafaring vessels, and moving millions of tons of cargo around the world, representing close to a fifth of the entire world’s shipping capacity. With the weapon NotPetya, all it took was one single computer to spread the deadly malware into a global supply chain shut-down. The attack paralyzed 17 of the company’s terminals in ports around the world, from New Jersey to Mumbai.“It was clear this problem was of a magnitude never seen before in global transport,” one Maersk customer remembers. “In the history of shipping IT, no one has ever gone through such a monumental crisis.”

The result was more than $10 billion in total damages (across all of the companies listed above), according to a White House assessment confirmed to WIRED by former Homeland Security adviser Tom Bossert.

The attack was orchestrated by a Russian military cyber unit as a part of their ongoing war with Ukraine. For years, Russia had used the country as a scorched-earth testing ground for new cyber weaponry. The NotPetya code that the hackers pushed out was honed to spread automatically, rapidly, and indiscriminately. “While there was no loss of life, [NotPetya] was the equivalent of using a nuclear bomb to achieve a small tactical victory,” says Bossert.

In the year since the attack, WIRED senior writer Andy Greenberg has traveled to Ukraine, Denmark, and Elizabeth, New Jersey, to report a blow-by-blow account of the experience at Maersk.

The narrative details the precise series of events that led to Maersk’s $300 million in damages, from the malware’s initial deployment in Ukraine, to the infection of a single Maersk computer in Odessa, to the shutdown of the company’s global network before the eyes of its helpless staff. Finally, the WIRED story offers a detailed account of the conglomerate’s desperate, weeks long recovery effort to bring its systems back online.

Executives from Maersk declined to comment in any official capacity for this story. WIRED’s account is instead assembled from current and former Maersk sources, many of whom chose to remain anonymous, as well as Ukrainian security experts who witnessed the attack and participated in the cyber recovery efforts.

The September cover story “The Code That Crashed the World” was written by WIRED's Andy Greenberg, and is adapted from his upcoming book Sandworm about the highly dangerous and brazen Kremlin cyber agents behind the NotPetya pandemic and two blackout-inducing cyberattacks in Ukraine.

*WIRED’s September issue is on national newsstands now

*Senior Writer Andy Greenberg available for interview from NYC