Azure RiskDetection flags riskyIPAddress from anonymous proxy IP addresses

Alerts when Azure reports user activity linked to a risky anonymous proxy IP address.

FreeReviewedSigma · High · v5

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

Initial Access → Defense Evasion

Recon
Resource Dev
Initial Access
- T1078Valid Accounts
Execution
Persistence
- T1078Valid Accounts
Priv Esc
- T1078Valid Accounts
Defense Evasion
- T1078Valid Accounts
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule identifies risk events where a user activity is associated with an IP address classified as an anonymous proxy. Attackers may use anonymous proxy infrastructure to obscure source identity and evade straightforward IP-based monitoring. The detection relies on Azure RiskDetection telemetry indicating a riskyIPAddress riskEventType tied to the anonymous proxy classification.

Reporting behind it

Related detections9 linkedT1078 — drag to rearrange

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Suspicious Success Login Attempt on a Windows OpenSSH Server (via security)

Suspicious SQL Server - Connection Attempt Using a Disabled Account (via application)

Suspicious Lateral Movement Detection - Based on "special Groups" Feature (via security)

Suspicious Snowflake Anomalous Client Application Associated With UNC5537 (via cloud)

Malicious Network Login Performed to Multiple Targets (via security)

Malicious RDP Reconnaissance with Valid Credentials Performed on Multiple Hosts (via security)

Malicious Local Administrator Added by Atera RMM Agent

Azure RiskDetection flags riskyIPAddress from anonymous proxy IP addresses

Pivot detection · T1078 · 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-user-activity-triggered-by-risky-anonymous-proxy-ip-be4d9c86

title: Azure RiskDetection flags riskyIPAddress from anonymous proxy IP addresses
id: e28af512-a8f2-40dd-9556-9b14e2df5222
status: test
description: This rule identifies risk events where a user activity is associated with an IP address classified as an anonymous proxy. Attackers may use anonymous proxy infrastructure to obscure source identity and evade straightforward IP-based monitoring. The detection relies on Azure RiskDetection telemetry indicating a riskyIPAddress riskEventType tied to the anonymous proxy classification.
references:
  - https://learn.microsoft.com/en-us/entra/id-protection/concept-identity-protection-risks#activity-from-anonymous-ip-address
  - 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_anonymous_ip_activity.yml
author: Mark Morowczynski '@markmorow', Gloria Lee, '@gleeiamglo', Huntrule Team
date: 2023-09-03
tags:
  - attack.stealth
  - attack.t1078
  - attack.persistence
  - attack.privilege-escalation
  - attack.initial-access
logsource:
  product: azure
  service: riskdetection
detection:
  selection:
    riskEventType: riskyIPAddress
  condition: selection
falsepositives:
  - We recommend investigating the sessions flagged by this detection in the context of other sign-ins from the user.
level: high
license: DRL-1.1
related:
  - id: be4d9c86-d702-4030-b52e-c7859110e5e8
    type: derived

Convert

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

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