Microsoft says massive Azure outage was caused by DDoS attack

Microsoft confirmed that a nine-hour worldwide outage impacting Microsoft 365 and multiple Azure services was triggered by a distributed denial-of-service (DDoS) attack; an error in the implementation of Microsoft’s DDoS protections amplified the impact, causing service degradation across Entra, Intune, Power BI, Azure App Services, and other services. Microsoft plans a Preliminary Post-Incident Review within 72 hours and a Final PIR within two weeks; attribution has not been established.