Manage Alert Suppression Rules
Implementation Effort: Low – Involves targeted configuration by security administrators within the Defender portal.
User Impact: Low – Suppression rules are managed by security teams; end users are not affected.
Overview
Managing alert suppression rules in Microsoft Defender for Servers allows security teams to reduce noise by hiding alerts that are known to be benign or expected in specific environments. This is especially useful for alerts triggered by legitimate tools or processes that are frequently used in your organization. Suppression rules can be created, edited, or deleted through the Microsoft Defender portal or via the Defender for Cloud REST API.
Administrators can define suppression criteria based on alert type, affected entities, and other metadata. These rules help streamline the alert triage process, allowing analysts to focus on high-priority threats. However, improper use of suppression rules can lead to missed detections, so it's important to review and audit these rules regularly.
This capability supports the "Verify Explicitly" principle of Zero Trust by ensuring that only relevant and verified alerts are surfaced for investigation, improving signal-to-noise ratio without compromising visibility.