GitHub Repo

Detection: Get First Occurrence and Last Occurrence of a MAC Address

REMOVED DETECTION

This detection has been removed from the Splunk Threat Research content library and is no longer maintained or supported.

Reason: As of Splunk Enterprise Security version 8.0, Splunk Enterprise Security no longer supports Investigations. As such, all Investigations have been deprecated in ES Content Update.

Removed in version: 5.2.0

If you have any questions or concerns, please reach out to us at research@splunk.com.

Updated Date: 2026-05-13 ID: bc91a8cf-35e7-4bb2-8140-e756cc06fd33 Author: Bhavin Patel, Splunk Type: Investigation Product: Splunk Enterprise Security

Description

This search allows you to gather more context around a notable which has detected a new device connecting to your network. Use this search to determine the first and last occurrences of the suspicious device attempting to connect with your network.

1
2| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Network_Sessions where nodename=All_Sessions.DHCP All_Sessions.signature=DHCPREQUEST All_Sessions.src_mac= $src_mac$ by All_Sessions.src_ip All_Sessions.user 
3| `security_content_ctime(lastTime)` 
4| `security_content_ctime(firstTime)`

Data Source

No data sources specified for this detection.

Macros Used

Name Value
security_content_summariesonly summariesonly=summariesonly_config allow_old_summaries=oldsummaries_config fillnull_value=fillnull_config``

Annotations

- MITRE ATT&CK
+ Kill Chain Phases
+ NIST
+ CIS
- Threat Actors
ID Technique Tactic

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting Value
Disabled true
Cron Schedule N/A
Earliest Time N/A
Latest Time N/A
Schedule Window N/A
Creates Finding (Notable) No
Creates Intermediate Finding (Risk Event) No

Implementation

To successfully implement this search, you must be ingesting the logs from your DHCP server.

Known False Positives

Associated Analytic Story

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Not Applicable N/A N/A N/A
Unit Not Applicable N/A N/A N/A
Integration Not Applicable N/A N/A N/A

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: GitHub |

Version: 1