AI-powered Submissions Response introduces generative AI explanations for admin email submissions

June 2025

• Defender for Office 365 is now able to detect and classify mail bombing attacks. Mail bombing is a distributed denial of service (DDoS) attack that typically subscribes recipients to a large number of legitimate newsletters and services. The resulting volume of incoming email within minutes intends to overwhelm the recipient's mailbox and email security systems, and acts as a precursor to malware, ransomware, or data exfiltration.
• Mail bombing is now an available Detection technology value in Threat Explorer, the Email entity page, and the Email summary panel. Mail bombing is also an available DetectionMethods value in Advanced Hunting.
• For more information, see MC1096885.
• AI-powered Submissions Response introduces generative AI explanations for admin email submissions to Microsoft. For more information, see Submission result definitions.