CrowdStrike said a problem with an update the company pushed to Falcon sensors on Windows hosts on July 18 caused a blue screen of death, an issue that coincided with a Microsoft Azure outage and widespread outages across airlines, banks, hospitals, and other services.

Our story on this incident: https://duo.com/decipher/crowdstrike-windows-update-linked-to-global-outages

The Windows monoculture paper: https://www.schneier.com/essays/archives/2003/09/cyberinsecurity_the.html