User impact: Suppression rules may be edited to unintentionally suppress more alerts in the Microsoft Defender 365 portal.
Current status: We've determined that a code regression is inadvertently causing edited suppression rules to unintentionally suppress more alerts in the Microsoft Defender 365 portal. In an attempt to prevent further impact, we've introduced validation logic which will prevent users from saving invalid rules which we suspect is causing impact. To further mitigate impact, we're working on a fix to address existing impact from rules already created that have suppressed other alerts. Scope of impact: Impact is specific to users who are served through the affected infrastructure. Root cause: A code regression is inadvertently causing edited suppression rules to unintentionally suppress more alerts in the Microsoft Defender 365 portal.
