Microsoft Defender for Office 365 will introduce prompt injection protection for email, detecting and quarantining malicious content targeting AI assistants. Rolling out from July to October 2026, it affects organizations with Defender Plan 2 or Microsoft 365 E5, enabling automatic high-confidence threat quarantine by default with no required action.
Applies to: Microsoft Defender XDR
Source: mc.merill.net — data via Merill Fernando's open archive (MIT).