On July 19, 2024, a global outage hit Windows PCs due to a problematic update from security firm CrowdStrike. The update to its Falcon service caused many systems to crash with the infamous “blue screen of death,” disrupting various services, including Microsoft 365.

The BBC reported that organizations such as Sky News and airlines like KLM were impacted. While some services have been restored, many are still undergoing fixes. Microsoft 365 experienced downtime from 10 PM last night due to a configuration change, affecting multiple services into the morning. This configuration change, involving CrowdStrike’s Falcon sensor, led to significant connectivity failures within Microsoft’s Azure backend, impacting downstream services.

CrowdStrike issued a workaround requiring users to boot PCs in safe mode and delete a system file from the CrowdStrike folder. This manual fix is necessary for systems that could not boot Windows normally.

Tom Henson, Managing Director at Emerge Digital, highlighted the extensive manual effort required to resolve this issue, emphasizing the challenges if systems are entirely offline. The incident underscores the risks associated with automatic updates, a feature intended to enhance security but potentially disruptive when faulty.

Mark Lloyd of Axians UK pointed out the broader implications of this outage, emphasizing global dependency on cloud services and the risks of centralized digital infrastructure. The outage affected critical sectors, including healthcare and emergency services, with older Windows systems being particularly vulnerable.

CrowdStrike clarified that the outage was not a cyberattack but a malfunction in a routine update. Nevertheless, the incident raises concerns about the potential damage from future cyber threats. This event serves as a stark reminder of the vulnerabilities inherent in our interconnected digital world and the need for robust, reliable infrastructure.