Azure Sign-in Auth Interruption: DeviceAuthenticationRequired/Failed and External Security Challenge

Alerts on Azure sign-in authentication interruptions tied to device authentication and external security challenge failures.

FreeReviewedSigma · Medium · v5

Product: azure
Service: signinlogs
Author: Austin Songer @austinsonger (SigmaHQ), DRL 1.1
Published: 2021-11-26
Updated: 2026-07-31

Analysis Detection

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 flags Azure sign-in events where authentication is interrupted or not completed, including cases indicating device authentication is required, device authentication failure, or an unsatisfied external security challenge. Attackers may force or exploit authentication breakpoints to evade access controls or disrupt sign-in flows before continuing with privilege escalation or persistence attempts. Detection relies on Azure sign-in log fields capturing specific ResultType values and their associated ResultDescription text.

Reporting behind it

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Azure Sign-in Auth Interruption: DeviceAuthenticationRequired/Failed and External Security Challenge

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-sign-in-authentication-interruption-via-device-and-external-security-chall-8366030e

title: "Azure Sign-in Auth Interruption: DeviceAuthenticationRequired/Failed and External Security Challenge"
id: 377addde-dbdb-41a5-be01-cfa882f38c8c
status: test
description: This rule flags Azure sign-in events where authentication is interrupted or not completed, including cases indicating device authentication is required, device authentication failure, or an unsatisfied external security challenge. Attackers may force or exploit authentication breakpoints to evade access controls or disrupt sign-in flows before continuing with privilege escalation or persistence attempts. Detection relies on Azure sign-in log fields capturing specific ResultType values and their associated ResultDescription text.
references:
  - https://learn.microsoft.com/en-us/entra/architecture/security-operations-privileged-accounts
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/azure/signin_logs/azure_unusual_authentication_interruption.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2021-11-26
modified: 2022-12-18
tags:
  - attack.privilege-escalation
  - attack.persistence
  - attack.initial-access
  - attack.stealth
  - attack.t1078
logsource:
  product: azure
  service: signinlogs
detection:
  selection_50097:
    ResultType: 50097
    ResultDescription: Device authentication is required
  selection_50155:
    ResultType: 50155
    ResultDescription: DeviceAuthenticationFailed
  selection_50158:
    ResultType: 50158
    ResultDescription: ExternalSecurityChallenge - External security challenge was not satisfied
  condition: 1 of selection_*
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: 8366030e-7216-476b-9927-271d79f13cf3
    type: derived

Convert

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

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