You may be right after all! Disputing Submission Responses in Microsoft Defender for Office 365

Introduction

As a Microsoft MVP (Most Valuable Professional) specializing in SIEM, XDR, and Cloud Security, I have witnessed the rapid evolution of cybersecurity technologies, especially those designed to protect organizations from sophisticated threats targeting email and collaboration tools. Microsoft Defender for Office 365 introduced an LLM-based engine to help better classify phishing emails that, these days, are mostly written using AI anyways about a year ago. Today, I'm excited to spotlight a new place AI has been inserted into a workflow to make it better…a feature that elevates the transparency and responsiveness of threat management: the ability to dispute a submission response directly within Microsoft Defender for Office 365. 

Understanding the Challenge  

While the automated and human-driven analyses are robust in Defender for Office 365, there are occasions where the response—be it a verdict of "benign" or "malicious"— doesn’t fully align with the security team's context or threat intelligence. If you are a Microsoft 365 organization with Exchange Online mailboxes, you’re probably familiar with how admins can use the Submissions page in the Microsoft Defender portal to submit messages, URLs, and attachments to Microsoft for analysis.  As a recent enhancement, now all the admin submissions use LLM based response for better explainability.

In the past, disputing such verdicts required separate support channels, using Community support, or manual email processes, often delaying resolution and impacting the speed of cyber operations, leaving many SOC analysts in Ricky and Lucy's place.... 

 Introducing the Dispute Submission Response Feature  

With the new dispute submission response feature, Microsoft Defender for Office 365 bridges a critical gap in the incident response workflow. Now, when a security analyst or administrator receives a verdict on a submitted item, they have the option to dispute the response directly within the Microsoft 365 Defender portal. This feature streamlines feedback, allowing teams to quickly flag disagreements and provide additional context for review at the speed of operations.  

  How It Works  

1. Upon submission of a suspicious item, Microsoft Defender for Office 365 provides a response indicating its assessment—malicious, benign, or other categorizations.  
2. If the security team disagrees with the verdict, they can select the "Dispute" option and submit their rationale, including supporting evidence and threat intelligence.  
3. The disputed case is escalated directly to Microsoft’s threat research team for further review, and the team is notified of progress and outcomes.  

This direct feedback loop not only empowers security teams to advocate for their organization's unique context, but also enables Microsoft to continually refine detection algorithms and verdict accuracy based on real-world input, because security is a team sport. 

Benefits for Security Operations  

• Faster Resolution: Streamlined dispute submission eliminates the need for external support tickets and escalations, reducing turnaround time for critical cases.  

• Greater Transparency: The feature fosters a collaborative relationship between customers and Microsoft, ensuring that verdicts are not final judgments but points in an ongoing dialogue.  

• Continuous Improvement: Feedback from disputes enhances Microsoft’s threat intelligence and improves detection for all Defender for Office 365 users.  

• Empowerment: Security teams gain a stronger voice in the protection of their environment, reinforcing trust in automated defenses.  

MVP Insights: Real-World Impact  

Having worked with global enterprises, I’ve seen how nuanced and context-specific threats can be. Sometimes, what appears benign to one organization may be a targeted attack for another, a slight modification to a URL may catch one email, but not others, as slight changes are made as billions of emails are sent. We are only as good as the consortium. The ability to dispute submission responses creates a vital safety net, ensuring that security teams are not forced to accept verdicts that could expose them to risk. It’s a welcome step toward adaptive, user-driven security operations.  

Conclusion  

The dispute submission response feature in Microsoft Defender for Office 365 is one of the most exciting features for me, because it focuses on enabling organizations striving for agility and accuracy in threat management. By enabling direct, contextual feedback, Microsoft empowers security teams to play an active role in shaping their defenses. As an MVP, I encourage all users to leverage this feature, provide detailed feedback, and help drive the future of secure collaboration in the cloud. You may be right after all.   

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This blog has been generously and expertly authored by Microsoft Security MVP, Mona Ghadiri with support of the Microsoft Defender for Office 365 product team.

Mona Ghadiri
Microsoft Security MVP 

Learn More and Meet the Author

1) December 16th Ask the Experts Webinar: 

Microsoft Defender for Office 365 | Ask the Experts: Tips and Tricks (REGISTER HERE)
DECEMBER 16, 8 AM US Pacific

You’ve watched the latest Microsoft Defender for Office 365 best practices videos and read the blog posts by the esteemed Microsoft Most Valuable Professionals (MVPs). Now bring your toughest questions or unique situations straight to the experts. In this interactive panel discussion, Microsoft MVPs will answer your real-world scenarios, clarify best practices, and highlight practical tips surfaced in the recent series. We’ll kick off with a who’s who and recent blog/video series recap, then dedicate most of the time to your questions across migration, SOC optimization, fine-tuning configuration, Teams protection, and even Microsoft community engagement. Come ready with your questions (or pre-submit here) for the expert Security MVPs on camera, or the Microsoft Defender for Office 365 product team in the chat! REGISTER NOW for 12/16. 

2) Additional MVP Tips and Tricks Blogs and Videos in this Four-Part Series: 

1. Safeguarding Microsoft Teams with Microsoft Defender for Office 365 by Pierre Thoor

2. Microsoft Defender for Office 365: Migration & Onboarding by Purav Desai 

3. (This post by Mona)

4. COMING SOON - Nov 12: Fine-tuning configuration

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