:warning: THIS IS A EXPERIMENTAL DETECTION

This detection has been marked experimental by the Splunk Threat Research team. This means we have not been able to test, simulate, or build datasets for this detection. Use at your own risk. This analytic is NOT supported.

Try in Splunk Security Cloud

Description

This hunting analytic identifies multiple failed logon attempts from a single IP. Use this analytic to identify patterns of suspicious logins from a single source and filter as needed or use this to drive tuning for higher fidelity analytics.

  • Type: Hunting

  • Product: Splunk Enterprise, Splunk Enterprise Security, Splunk Cloud

  • Last Updated: 2022-09-21
  • Author: Michael Haag, Rico Valdez, Splunk
  • ID: 19cba45f-cad3-4032-8911-0c09e0444552

Annotations

ATT&CK

ATT&CK

ID Technique Tactic
T1078 Valid Accounts Defense Evasion, Persistence, Privilege Escalation, Initial Access
T1078.001 Default Accounts Defense Evasion, Persistence, Privilege Escalation, Initial Access
Kill Chain Phase
  • Exploitation
  • Installation
  • Delivery
NIST
  • DE.AE
CIS20
  • CIS 10
CVE 


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`okta` outcome.reason=INVALID_CREDENTIALS 
| rename client.geographicalContext.country as country, client.geographicalContext.state as state, client.geographicalContext.city as city 
| stats min(_time) as firstTime max(_time) as lastTime dc(src_user) as distinct_users values(src_user) as users by src_ip, displayMessage, outcome.reason, country, state, city 
| `security_content_ctime(firstTime)` 
| `security_content_ctime(lastTime)` 
| search distinct_users > 5
| `multiple_okta_users_with_invalid_credentials_from_the_same_ip_filter`

Macros

The SPL above uses the following Macros:

:information_source: multiple_okta_users_with_invalid_credentials_from_the_same_ip_filter is a empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Required fields

List of fields required to use this analytic.

  • _time
  • outcome.reason
  • client.geographicalContext.country
  • client.geographicalContext.state
  • client.geographicalContext.city
  • user
  • src_ip
  • displayMessage

How To Implement

This search is specific to Okta and requires Okta logs are being ingested in your Splunk deployment.

Known False Positives

A single public IP address servicing multiple legitmate users may trigger this search. In addition, the threshold of 5 distinct users may be too low for your needs. You may modify the included filter macro multiple_okta_users_with_invalid_credentials_from_the_same_ip_filter to raise the threshold or except specific IP adresses from triggering this search.

Associated Analytic Story

RBA

Risk Score Impact Confidence Message
9.0 30 30 Multple user accounts have failed to authenticate from a single IP.

:information_source: The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

Reference

Test Dataset

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

source | version: 3