Microsoft Entra Agent ID Flaw Enabled Tenant Takeover via Privilege Escalation

Silverfort researchers found a scope misconfiguration in Microsoft Entra Agent ID: the Agent ID Administrator role could add itself as owner to non-agent Service Principals, inject credentials (passwords/certificates), and authenticate as those applications, enabling full tenant takeover. A demo showed a Global Administrator account hijack. The flaw was reported in late Feb/early Mar 2026, confirmed by Microsoft, and a fix was deployed by 9 April 2026; organizations are advised to audit ownership changes and new secrets on sensitive accounts.