Microsoft last week leaked Office 365 users names and email addresses across multi-tenant admin dashboards, according to Petri. The breach affected users in multiple Office 365 data center regions, including both the United States and EMEA.Initially, several Office 365 administrators reported that the email and SharePoint usage for their tenants increased. When these admins evaluated the underlying data, they saw that it included users from one or more domains outside their tenant.Microsoft has fixed the problem, and usage reports are back online and working properly, Petri reported.Determine whether Microsoft's native capabilities are sufficient based on how an organization uses Microsoft services. Examine third-party alternatives if gaps prevent an organization from implementing its security and compliance policies. Deploy an identity, access and privilege management strategy. Implement visibility, data security, threat protection and device management controls using native Office 365 capabilities; if necessary, these capabilities can be enhanced with third-party products. Use a CASB to implement consistent security policies across all Office 365 services and other non-Microsoft SaaS applications. Gartner has predicted 40 percent of Office 365 deployments will rely on third-party tools to fill gaps in security and compliance by 2018.In addition, 50 percent of organizations using Office 365 will rely on non-Microsoft security tools to maintain consistent security policies across their multivendor "SaaSscape" by 2020, according to Gartner.Meta Description: Microsoft suffers a data breach that reveals the names & email addresses of Office 365 users from the United States, EMEA & other data center regions.