The disruption began quietly, at the level of a single software file. At 04:09 UTC on Friday, July 19, 2024, an update to CrowdStrike’s Falcon security software pushed a faulty driver to computers running Microsoft Windows, and machines around the world crashed into the blue screen of death, many stuck restarting endlessly. Systems running Mac or Linux were not affected. The morning that followed brought long lines, frozen screens and grounded airplanes.
The encouraging part is what this was not. It was not a breach and not an attack. CrowdStrike chief executive George Kurtz said in a statement on social media: “CrowdStrike is actively working with customers impacted by a defect found in a single content update for Windows hosts. Mac and Linux hosts are not impacted. This is not a security incident or cyberattack. The issue has been identified, isolated and a fix has been deployed,” The timeline checks out: the faulty update was reverted at 05:27 UTC, and by 09:45 UTC Kurtz had confirmed the fix was deployed.
Airlines felt it first. American, United and Delta asked the Federal Aviation Administration for a global ground stop on all their flights on Friday morning, according to an FAA alert. Planes already in the air were allowed to continue, but nothing new was taking off. “While we work to restore those systems, we are holding all aircraft at their departure airports. Flights already airborne are continuing to their destinations.” United said. American said a vendor’s technical issue had hit several carriers at once and that it had safely re-established its operation by 5 a.m. Eastern time. The count climbed: at least 540 U.S. flights already cancelled as of 6:25 a.m. Eastern, roughly 1,500 U.S. cancellations and more than 1,000 worldwide by midday. In India, airlines fell back on handwritten boarding passes; at Hong Kong’s airport, staff held up handwritten signs to direct passengers.
The reach went well beyond aviation. The London Stock Exchange, Berlin’s airport and Gatwick in London all reported disruption. Hospitals were hit too, and this is where patients should pay attention: Mass General Brigham in Boston called off all elective surgeries for the day, and Cincinnati Children’s Hospital Medical Center reported disruptions of its own. Patients with procedures that day had to call ahead.
Recovery is manual labor. Technicians must boot each affected machine into safe mode and delete the faulty driver file, one computer at a time, work that can take days for large organizations. One passenger, delayed two hours on the tarmac at SeaTac before deplaning, told ABC News: “No one here knows anything, the gate agents said we all know as much as they do,” Travelers should confirm a flight’s status before leaving home and keep receipts for meals or hotels, but the cause was identified, isolated and fixed within hours.
Sources
- Is Your Flight Delayed by the Tech Outage? Here’s What You Need to Know. – The New York Times
- Tech outage eases after widespread disruption | Reuters
- CrowdStrike outage sparks global chaos with airline, bank and other disruptions – ABC News (By Sam Sweeney and Jon Haworth, July 19, 2024, 2:41 AM ET = 06:41 UTC; Wayback capture 2024-07-19T12:57:44Z proves this text live 2h02m before the 15:00 UTC post)
