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Unusual Hour for a User to Logon

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Unusual Hour for a User to Logon

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A machine learning job detected a user logging in at a time of day that is unusual for the user. This can be due to credentialed access via a compromised account when the user and the threat actor are in different time zones. In addition, unauthorized user activity often takes place during non-business hours.

Rule type: machine_learning

Machine learning job: auth_rare_hour_for_a_user

Machine learning anomaly threshold: 75

Severity: low

Risk score: 21

Runs every: 15 minutes

Searches indices from: now-30m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

https://www.elastic.co/guide/en/security/current/prebuilt-ml-jobs.html

Tags:

Elastic
Authentication
Threat Detection
ML
Initial Access

Version: 100 (version history)

Added (Elastic Stack release): 7.14.0

Last modified (Elastic Stack release): 8.5.0

Rule authors: Elastic

Rule license: Elastic License v2

Potential false positives

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Users working late, or logging in from unusual time zones while traveling, may trigger this rule. ==== Threat mapping

Framework: MITRE ATT&CK^TM

Tactic:
- Name: Initial Access
- ID: TA0001
- Reference URL: https://attack.mitre.org/tactics/TA0001/
Technique:
- Name: Valid Accounts
- ID: T1078
- Reference URL: https://attack.mitre.org/techniques/T1078/

Rule version history

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Version 100 (8.5.0 release)

Formatting only

Version 2 (8.4.0 release)

Formatting only

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