Azure Entra ID Riskdetection: Anonymous IP Address sign-in risk events

Detects Azure sign-in risk events labeled as anonymized/anonymous IP addresses.

FreeReviewedSigma · High · v5

Product: azure
Service: riskdetection
Author: Gloria Lee, '@gleeiamglo' (SigmaHQ), DRL 1.1
Published: 2023-08-22
Updated: 2026-07-31

ATT&CK techniques

Cred Access

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
- T1528Steal Application Access Token
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule flags sign-in risk events where the risk event type indicates an anonymized/anonymous IP address, such as activity attributed to an anonymous browser or VPN. Attackers may use anonymity services to reduce traceability and increase the chances of successful credential access. It relies on Azure Entra ID risk detection telemetry, specifically the risk event type value recorded for each risk event.

Reporting behind it

Related detections9 linkedT1528 — drag to rearrange

Malicious OAuth Application Granted Full Mailbox and EWS Permissions (via m365)

Suspicious GAM OAuth Token Enumeration via Process Creation

Suspicious Entra ID Device Code Flow Authentication

Suspicious Delegated Permission Grant to Entra Agent Access Scope via Azure Audit Logs

Suspicious OAuth Application Registration with Localhost Reply URL via Azure AD

Malicious PRT Token Forging via AADInternals (via ps_script)

Possible VMware Workspace ONE SSRF via instanceHealth hostName At-Injection (via webserver)

Suspicious Entra Device Code Authentication with Office Client and Automated User Agent

Suspicious Access to Kubernetes Service Account Token via Curl or Wget (via process_creation)

Azure Entra ID Riskdetection: Anonymous IP Address sign-in risk events

Pivot detection · T1528 · 9 related

Changelog

v5
Candidate ingested via manual entry.2026-07-31
v4
Candidate ingested via manual entry.2026-07-31
v3
Candidate ingested via manual entry.2026-07-31
v2
Candidate ingested via manual entry.2026-07-31
v1
No 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.

azure-riskdetection-anonymous-ip-address-sign-ins-53acd925

title: "Azure Entra ID Riskdetection: Anonymous IP Address sign-in risk events"
id: 80572e00-e16b-4f4f-8a87-5e1c0715cf2e
status: test
description: This rule flags sign-in risk events where the risk event type indicates an anonymized/anonymous IP address, such as activity attributed to an anonymous browser or VPN. Attackers may use anonymity services to reduce traceability and increase the chances of successful credential access. It relies on Azure Entra ID risk detection telemetry, specifically the risk event type value recorded for each risk event.
references:
  - https://learn.microsoft.com/en-us/graph/api/resources/riskdetection?view=graph-rest-1.0
  - https://learn.microsoft.com/en-us/entra/id-protection/concept-identity-protection-risks#anonymous-ip-address
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/identity_protection/azure_identity_protection_anonymous_ip_address.yml
author: Gloria Lee, '@gleeiamglo', Huntrule Team
date: 2023-08-22
tags:
  - attack.t1528
  - attack.credential-access
logsource:
  product: azure
  service: riskdetection
detection:
  selection:
    riskEventType: anonymizedIPAddress
  condition: selection
falsepositives:
  - We recommend investigating the sessions flagged by this detection in the context of other sign-ins
level: high
license: DRL-1.1
related:
  - id: 53acd925-2003-440d-a1f3-71a5253fe237
    type: derived

Convert

This rule as a query you can run. Uses no unlock credit.

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