Detect Use of Stolen Web Session Cookies Across Platforms

Technique Detected:  Web Session Cookie | T1550.004

ID: DET0074
Domains: Enterprise
Analytics: AN0201, AN0202, AN0203
Version: 1.0
Created: 21 October 2025
Last Modified: 21 October 2025

Analytics

AN0201

Anomalous access to cloud web applications using session tokens without corresponding MFA/credential validation, often from unusual locations or device fingerprints.

Log Sources
Data Component Name Channel
Web Credential Usage (DC0007) AWS:CloudTrail SessionToken used without preceding MFA or login event
Logon Session Creation (DC0067) AWS:CloudTrail ConsoleLogin
Mutable Elements
Field Description
TimeWindow How far back to check for legitimate MFA or login events before token usage
IPGeolocationDistance Threshold for flagging geographically impossible logins

AN0202

Session cookie reuse on unmanaged browsers, devices, or client types deviating from user baseline (e.g., switching from Chrome to curl).

Log Sources
Data Component Name Channel
Web Credential Usage (DC0007) m365:unified SessionId reused from different device/browser fingerprint
User Account Authentication (DC0002) saas:okta session.impersonation.start
Mutable Elements
Field Description
BrowserFingerprintMatch Tolerance for accepting small differences in user-agent headers
SessionReuseTimeout Time gap threshold between valid session creation and reuse

AN0203

Web session tokens reused in native Office apps (e.g., Outlook, Teams) without associated token refresh or login behavior on the endpoint.

Log Sources
Data Component Name Channel
Logon Session Creation (DC0067) m365:unified UserLoggedIn
Mutable Elements
Field Description
EndpointTokenSyncGap Allowed delta between endpoint login and cloud token reuse