Okta Suspicious Use of a Session Cookie

name: Okta Suspicious Use of a Session Cookie
id: 71ad47d1-d6bd-4e0a-b35c-020ad9a6959e
version: 12
creation_date: '2024-04-17'
modification_date: '2026-05-13'
author: Scott Dermott, Felicity Robson, Okta, Michael Haag, Bhavin Patel, Splunk
status: production
type: Anomaly
description: The following analytic identifies suspicious use of a session cookie by detecting multiple client values (IP, User Agent, etc.) changing for the same Device Token associated with a specific user. It leverages policy evaluation events from successful authentication logs in Okta. This activity is significant as it may indicate an adversary attempting to reuse a stolen web session cookie, potentially bypassing authentication mechanisms. If confirmed malicious, this could allow unauthorized access to user accounts, leading to data breaches or further exploitation within the environment.
data_source:
    - Okta
search: |-
    `okta` eventType IN (policy.evaluate_sign_on) outcome.result IN (ALLOW, SUCCESS)
      | stats earliest(_time) as _time, values(client.ipAddress) as src_ip, values(client.userAgent.rawUserAgent) as user_agent, values(client.userAgent.os) as userAgentOS_list, values(client.geographicalContext.city) as city, values(client.userAgent.browser) as userAgentBrowser_list, values(device.os_platform) as okta_device_os, dc(client.userAgent.browser) as dc_userAgentBrowser, dc(client.userAgent.os) as dc_userAgentOS, dc(client.ipAddress) as dc_src_ip, values(outcome.reason) as reason values(dest) as dest
        BY debugContext.debugData.dtHash, user
      | where dc_src_ip>1 AND (dc_userAgentOS>1 OR dc_userAgentBrowser>1)
      | `okta_suspicious_use_of_a_session_cookie_filter`
how_to_implement: This detection utilizes logs from Okta Identity Management (IM) environments. It requires the ingestion of OktaIm2 logs through the Splunk Add-on for Okta Identity Cloud (https://splunkbase.splunk.com/app/6553).
known_false_positives: False positives may occur, depending on the organization's size and the configuration of Okta.
references:
    - https://attack.mitre.org/techniques/T1539/
intermediate_findings:
    entities:
        - field: user
          type: user
          score: 20
          message: A user [$user$] is attempting to use a session cookie from multiple IP addresses or devices. Investigate further to determine if this was authorized.
analytic_story:
    - Suspicious Okta Activity
    - Okta Account Takeover
    - Scattered Lapsus$ Hunters
asset_type: Okta Tenant
mitre_attack_id:
    - T1539
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: application
security_domain: identity