Suspicious Inbox Forwarding
Detects when a Microsoft Cloud App Security reported suspicious email forwarding rules, for example, if a user created an inbox rule that forwards a copy of all emails to an external address.
Sigma rule (View on GitHub)
1title: Suspicious Inbox Forwarding
2id: 6c220477-0b5b-4b25-bb90-66183b4089e8
3status: test
4description: Detects when a Microsoft Cloud App Security reported suspicious email forwarding rules, for example, if a user created an inbox rule that forwards a copy of all emails to an external address.
5references:
6 - https://learn.microsoft.com/en-us/defender-cloud-apps/anomaly-detection-policy
7 - https://learn.microsoft.com/en-us/defender-cloud-apps/policy-template-reference
8author: Austin Songer @austinsonger
9date: 2021-08-22
10modified: 2022-10-09
11tags:
12 - attack.exfiltration
13 - attack.t1020
14logsource:
15 service: threat_management
16 product: m365
17detection:
18 selection:
19 eventSource: SecurityComplianceCenter
20 eventName: 'Suspicious inbox forwarding'
21 status: success
22 condition: selection
23falsepositives:
24 - Unknown
25level: low
References
Related rules
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