---
title: Impossible travel event observed across multiple sources
description: Datadog, the leading service for cloud-scale monitoring.
breadcrumbs: >-
  Docs > Datadog Security > OOTB Rules > Impossible travel event observed across
  multiple sources
---

# Impossible travel event observed across multiple sources
Classification:attackTactic:[TA0001-initial-access](https://attack.mitre.org/tactics/TA0001)Technique:[T1078-valid-accounts](https://attack.mitre.org/techniques/T1078) 
## Goal{% #goal %}

Detect when unusual authentication attempts from different geo locations are made from a single user.

## Strategy{% #strategy %}

The Impossible Travel detection type's algorithm compares the GeoIP data of the last log and the current log to determine if the user `{{@ocsf.user.email_addr}}` traveled more than 500km at over 1,000km/h. This detection rule aims to identify potential threats early, allowing for timely investigation and mitigation to protect server resources and maintain service availability. This rule specifically compares logins **across** sources, alerting on impossible travel scenarios across multiple applications.

## Triage and response{% #triage-and-response %}

1. Investigate the source user `{{@ocsf.user.email_addr}}` with a request from different geo location from `{{@impossible_travel.triggering_locations.first_location.city}}, {{@impossible_travel.triggering_locations.first_location.country}}` and `{{@impossible_travel.triggering_locations.second_location.city}}, {{@impossible_travel.triggering_locations.second_location.country}}`.
1. Implement immediate measures to block or limit the impact of the suspicious activity if confirmed as a threat.
1. Use the Cloud SIEM - User Investigation dashboard to audit any user actions that may have occurred after the illegitimate login.