Azure Sign-in Logs: Conditional Access Blocks User Token Issuance (ResultType 53003)

Flags Azure sign-in attempts blocked by Conditional Access due to token issuance denial.

FreeReviewedSigma · Medium · v5
Product
azure
Service
signinlogs
Author
AlertIQ (SigmaHQ), DRL 1.1
Published
2021-10-10
Updated
2026-07-31
title: "Azure Sign-in Logs: Conditional Access Blocks User Token Issuance (ResultType 53003)"
id: 7b826530-134c-4ec0-8d5f-7351d0a23946
status: test
description: This rule matches Azure sign-in events where access was blocked by Conditional Access policies, specifically when token issuance is not allowed (ResultType 53003). Attackers may use stolen or guessed credentials to attempt sign-ins, and Conditional Access blocking can signal such unauthorized attempts against valid accounts. The detection relies on Azure sign-in log telemetry, using the ResultType field to identify blocked access outcomes.
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_user_login_blocked_by_conditional_access.yml
author: AlertIQ, Huntrule Team
date: 2021-10-10
modified: 2022-12-25
tags:
  - attack.privilege-escalation
  - attack.persistence
  - attack.credential-access
  - attack.initial-access
  - attack.stealth
  - attack.t1110
  - attack.t1078.004
logsource:
  product: azure
  service: signinlogs
detection:
  selection:
    ResultType: 53003
  condition: selection
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: 9a60e676-26ac-44c3-814b-0c2a8b977adf
    type: derived