Name:Cisco Duo Admin Login Unusual Browser id:b38932ad-e663-4e90-bfdf-8446ee5b3f34 version:6 date:None author:Patrick Bareiss, Splunk status:production type:TTP Description:The following analytic identifies instances where a Duo admin logs in using a browser other than Chrome, which is considered unusual based on typical access patterns. Please adjust as needed to your environment. The detection leverages Duo activity logs ingested via the Cisco Security Cloud App and filters for admin login actions where the browser is not Chrome. By renaming and aggregating relevant fields such as user, browser, IP address, and location, the analytic highlights potentially suspicious access attempts that deviate from the norm. This behavior is significant for a SOC because the use of an unexpected browser may indicate credential compromise, session hijacking, or the use of unauthorized devices by attackers attempting to evade detection. Detecting such anomalies enables early investigation and response, helping to prevent privilege escalation, policy manipulation, or further compromise of sensitive administrative accounts. The impact of this attack could include unauthorized changes to security policies, user access, or the disabling of critical security controls, posing a substantial risk to the organizations security posture. Data_source:
-Cisco Duo Activity
search:`cisco_duo_activity` "action.name"=admin_login NOT access_device.browser IN (Chrome)
| rename actor.name as user access_device.ip.address as src_ip
| stats count min(_time) as firstTime max(_time) as lastTime BY access_device.browser access_device.browser_version src_ip access_device.location.city access_device.location.country access_device.location.state access_device.os access_device.os_version actor.details actor.type outcome.result user
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `cisco_duo_admin_login_unusual_browser_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' analytic_story:['Cisco Duo Suspicious Activity']
