LoFP / a malware filter policy may be deleted by a system or network administrator. verify that the configuration change was expected. exceptions can be added to this rule to filter expected behavior.

Techniques

• T1562

Sample rules

Microsoft 365 Exchange Malware Filter Policy Deletion

• source: elastic
• technicques:
  • T1562

Description

Identifies when a malware filter policy has been deleted in Microsoft 365. A malware filter policy is used to alert administrators that an internal user sent a message that contained malware. This may indicate an account or machine compromise that would need to be investigated. Deletion of a malware filter policy may be done to evade detection.

Detection logic

event.dataset:o365.audit and event.provider:Exchange and event.category:web and event.action:"Remove-MalwareFilterPolicy" and event.outcome:success