Azure risk event: Suspicious inbox manipulation rules that delete or move messages or folders
Alerts on Azure risk events for suspicious inbox rules that delete or move mailbox items.
- Product
- azure
- Service
- riskdetection
- Author
- Mark Morowczynski '@markmorow', Gloria Lee, '@gleeiamglo' (SigmaHQ), DRL 1.1
- Published
- 2023-09-03
- Updated
- 2026-07-31
ATT&CK techniques
Defense EvasionRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule flags an Azure risk detection event indicating suspicious inbox manipulation rules that delete or move messages or folders within a user’s inbox. Attackers can use inbox rules to hide their activity, reroute communications, or degrade user visibility while maintaining persistence. The detection relies on Azure risk telemetry with the riskEventType value mcasSuspiciousInboxManipulationRules.
Reporting behind it
- learn.microsoft.comhttps://learn.microsoft.com/en-us/entra/id-protection/concept-identity-protection-risks#suspicious-inbox-manipulation-rules
- learn.microsoft.comhttps://learn.microsoft.com/en-us/entra/architecture/security-operations-user-accounts#unusual-sign-ins
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/identity_protection/azure_identity_protection_inbox_manipulation.yml
Changelog
v5- v5Candidate ingested via manual entry.2026-07-31
- v4Candidate ingested via manual entry.2026-07-31
- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No changelog recorded for this version.2026-07-30
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
title: "Azure risk event: Suspicious inbox manipulation rules that delete or move messages or folders"
id: 2f580dbd-0e59-4acd-9b82-42b2019cf275
status: test
description: This rule flags an Azure risk detection event indicating suspicious inbox manipulation rules that delete or move messages or folders within a user’s inbox. Attackers can use inbox rules to hide their activity, reroute communications, or degrade user visibility while maintaining persistence. The detection relies on Azure risk telemetry with the riskEventType value mcasSuspiciousInboxManipulationRules.
references:
- https://learn.microsoft.com/en-us/entra/id-protection/concept-identity-protection-risks#suspicious-inbox-manipulation-rules
- https://learn.microsoft.com/en-us/entra/architecture/security-operations-user-accounts#unusual-sign-ins
- https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/identity_protection/azure_identity_protection_inbox_manipulation.yml
author: Mark Morowczynski '@markmorow', Gloria Lee, '@gleeiamglo', Huntrule Team
date: 2023-09-03
tags:
- attack.stealth
- attack.t1140
logsource:
product: azure
service: riskdetection
detection:
selection:
riskEventType: mcasSuspiciousInboxManipulationRules
condition: selection
falsepositives:
- Actual mailbox rules that are moving items based on their workflow.
level: high
license: DRL-1.1
related:
- id: ceb55fd0-726e-4656-bf4e-b585b7f7d572
type: derived