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

ATT&CK techniques

Initial Access → Cred Access
  1. Recon

  2. Resource Dev

  3. Execution

  4. Cred Access

  5. Discovery

  6. Lateral Movement

  7. Collection

  8. C2

  9. Exfiltration

  10. Impact

What it detects

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.

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Azure Sign-in Logs: Conditional Access Blocks User Token Issuance (ResultType 53003)
Pivot detection · T1078.004 · 9 related

Changelog

v5
  1. v5
    Candidate ingested via manual entry.2026-07-31
  2. v4
    Candidate ingested via manual entry.2026-07-31
  3. v3
    Candidate ingested via manual entry.2026-07-31
  4. v2
    Candidate ingested via manual entry.2026-07-31
  5. 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.