The recent CrowdStrike outage affected approximately 8.5 million devices, less than 1% of Windows computers worldwide, according to a blog post by David Weston, corporate vice president of enterprise and OS security at Microsoft.
This is the first real-world figure from Microsoft or CrowdStrike on the scale of yesterday’s outage, which was caused by an update to CrowdStrike’s cybersecurity software that crashed Windows devices (Mac and Linux devices were not affected).
Although the number of affected devices was relatively small, the disruption was widespread and global, affecting banks, retailers, brokerages, and railway networks. Airlines suspended flights worldwide.
“While the percentage of affected devices was small, the broad economic and societal impact reflects the fact that many companies that run critical services rely on CrowdStrike,” Weston wrote.
He did not say what percentage of Windows machines with CrowdStrike software installed were affected. It’s also worth noting that even a single computer failure could potentially take down an entire network or data center.
Weston also wrote that while “this was not a Microsoft incident,” the company was working with CrowdStrike to address the issue. System recovery could be slow if manual remediation is required for all affected computers, but Weston said Microsoft and CrowdStrike have developed a “scalable solution that will help accelerate remediation using Microsoft’s Azure infrastructure,” and are also working with Amazon Web Services and Google Cloud Platform.
