Detection: Splunk list all nonstandard admin accounts

EXPERIMENTAL DETECTION

This detection status is set to experimental. The Splunk Threat Research team has not yet fully tested, simulated, or built comprehensive datasets for this detection. As such, this analytic is not officially supported. If you have any questions or concerns, please reach out to us at research@splunk.com.

Updated Date: 2024-10-17 ID: 401d689c-8596-4c6b-a710-7b6fdca296d3 Author: Rod Soto Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic identifies nonstandard Splunk accounts with administrative rights on the instance, excluding the default admin account. It uses REST API calls to retrieve user data and filters for accounts with admin capabilities. This activity is significant as unauthorized admin accounts can indicate potential security breaches or misconfigurations. If confirmed malicious, attackers could leverage these accounts to execute commands, escalate privileges, or persist within the environment, posing a significant risk to the integrity and security of the Splunk instance.

1
2| rest splunk_server=local /services/authentication/users 
3|search capabilities=admin* OR imported_capabilities=admin* title!=admin 
4| table title roles capabilities splunk_server 
5| `splunk_list_all_nonstandard_admin_accounts_filter`

Data Source

Name Platform Sourcetype Source
Splunk Splunk icon Splunk 'splunkd_ui_access' 'splunkd_ui_access.log'

Macros Used

Name Value

| splunk_list_all_nonstandard_admin_accounts_filter | search * |

splunk_list_all_nonstandard_admin_accounts_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK
+ Kill Chain Phases
+ NIST
+ CIS
- Threat Actors
ID Technique Tactic
T1189 Drive-by Compromise Initial Access
KillChainPhase.DELIVERY
NistCategory.DE_AE
Cis18Value.CIS_10
APT19
APT28
APT32
APT37
APT38
Andariel
Axiom
BRONZE BUTLER
CURIUM
Daggerfly
Dark Caracal
Darkhotel
Dragonfly
Earth Lusca
Elderwood
Lazarus Group
Leafminer
Leviathan
Machete
Magic Hound
Mustard Tempest
PLATINUM
PROMETHIUM
Patchwork
RTM
Threat Group-3390
Transparent Tribe
Turla
Windigo
Windshift
Winter Vivern

Default Configuration

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

Setting Value
Disabled true
Cron Schedule 0 * * * *
Earliest Time -70m@m
Latest Time -10m@m
Schedule Window auto
Creates Risk Event False
This configuration file applies to all detections of type hunting.

Implementation

The user running this search is required to have a permission allowing them to dispatch REST requests to indexers (the dispatch_rest_to_indexers capability) in some architectures. If there have been admin account, in addition to the standard admin account, intentionally created on this server, then edit the filter macro to exclude them.

Known False Positives

It is not possible to discern from the user table whether or not users with admin rights have been created intentionally, accidentally, or as a result of exploitation. Each user with these rights should be investigated and, if legitimate, added to the filter macro above. If a user is not believed to be legitimate, then further investigation should take place.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Potential stored XSS attempt from $host$ 25 50 50
The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

References

Detection Testing

Test Type Status Dataset Source Sourcetype
Validation Not Applicable N/A N/A N/A
Unit ❌ Failing N/A N/A N/A
Integration ❌ Failing 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: 3