Okta FastPass blocks phishing authentication attempts via MFA
Alerts on Okta FastPass MFA failures where the declined reason indicates a known phishing attempt.
- Product
- okta
- Service
- okta
- Author
- Austin Songer @austinsonger (SigmaHQ), DRL 1.1
- Published
- 2023-05-07
- Updated
- 2026-07-31
ATT&CK techniques
Initial AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule identifies Okta authentication events where MFA using FastPass is declined with the reason "FastPass declined phishing attempt". Attackers attempting to use known phishing pages are likely to trigger this failure behavior, making it a useful signal for initial access attempts. It relies on Okta System Log telemetry fields including event type, outcome result, and outcome reason.
Reporting behind it
- sec.okta.comhttps://sec.okta.com/fastpassphishingdetection
- developer.okta.comhttps://developer.okta.com/docs/reference/api/system-log/
- developer.okta.comhttps://developer.okta.com/docs/reference/api/event-types/
- github.comhttps://github.com/SigmaHQ/sigma/blob/master/rules/identity/okta/okta_fastpass_phishing_detection.yml
Changelog
v4- v4Candidate ingested via manual entry.2026-07-31
- v3Candidate ingested via manual entry.2026-07-31
- v2Candidate ingested via manual entry.2026-07-31
- v1No 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.
title: Okta FastPass blocks phishing authentication attempts via MFA
id: 5c08e762-946a-49ec-ba53-458b143c353c
status: test
description: This rule identifies Okta authentication events where MFA using FastPass is declined with the reason "FastPass declined phishing attempt". Attackers attempting to use known phishing pages are likely to trigger this failure behavior, making it a useful signal for initial access attempts. It relies on Okta System Log telemetry fields including event type, outcome result, and outcome reason.
references:
- https://sec.okta.com/fastpassphishingdetection
- https://developer.okta.com/docs/reference/api/system-log/
- https://developer.okta.com/docs/reference/api/event-types/
- https://github.com/SigmaHQ/sigma/blob/master/rules/identity/okta/okta_fastpass_phishing_detection.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2023-05-07
modified: 2026-04-27
tags:
- attack.initial-access
- attack.t1566
logsource:
product: okta
service: okta
detection:
selection:
outcome.reason: FastPass declined phishing attempt
outcome.result: FAILURE
eventType: user.authentication.auth_via_mfa
condition: selection
falsepositives:
- Unlikely
level: high
license: DRL-1.1
related:
- id: ee39a9f7-5a79-4b0a-9815-d36b3cf28d3e
type: derived