Cisco Duo Policy Bypass 2FA

name: Cisco Duo Policy Bypass 2FA
id: 65862e8a-799a-4509-ae1c-4602aa139580
version: 6
creation_date: '2025-07-10'
modification_date: '2026-05-13'
author: Patrick Bareiss, Splunk
status: production
type: TTP
description: The following analytic detects instances where a Duo policy is created or updated to allow access without two-factor authentication (2FA). It identifies this behavior by searching Duo administrator activity logs for policy changes that set the authentication status to "Allow access without 2FA." By monitoring for these specific actions, the analytic highlights potential attempts to weaken authentication controls, which could be indicative of malicious activity or insider threats. This behavior is critical for a SOC to identify, as bypassing 2FA significantly reduces the security posture of an organization, making it easier for attackers to gain unauthorized access to sensitive systems and data. Detecting and responding to such policy changes promptly helps prevent potential account compromise and mitigates the risk of broader security breaches.
data_source:
    - Cisco Duo Administrator
search: |-
    `cisco_duo_administrator` action=policy_update OR action=policy_create
      | spath input=description
      | search auth_status="Allow access without 2FA"
      | rename object as user
      | stats count min(_time) as firstTime max(_time) as lastTime
        BY action actionlabel description
           user admin_email
      | `security_content_ctime(firstTime)`
      | `security_content_ctime(lastTime)`
      | `cisco_duo_policy_bypass_2fa_filter`
how_to_implement: The analytic leverages Duo activity logs to be ingested using the Cisco Security Cloud App (https://splunkbase.splunk.com/app/7404).
known_false_positives: No false positives have been identified at this time.
references:
    - https://splunkbase.splunk.com/app/7404
drilldown_searches:
    - name: View the detection results for - "$user$"
      search: '%original_detection_search% | search  user = "$user$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
finding:
    title: A policy has been created or updated to allow access without 2FA by user $user$ with email $admin_email$
    entity:
        field: user
        type: user
        score: 50
analytic_story:
    - Cisco Duo Suspicious Activity
asset_type: Identity
mitre_attack_id:
    - T1556
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: application
security_domain: identity
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1556/cisco_duo_policy_bypass_2FA/cisco_duo_administrator.json
          source: duo
          sourcetype: cisco:duo:administrator
      test_type: unit