GitHub Repo

Detection: Splunk RCE via External Lookup Copybuckets

REMOVED DETECTION

This detection has been removed from the Splunk Threat Research content library and is no longer maintained or supported.

Reason: Detection is deprecated as the associated CVEs have been patched in the latest Splunk release.

Removed in version: 5.6.0

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

Updated Date: 2026-05-14 ID: 8598f9de-bba8-42a4-8ef0-12e1adda4131 Author: Rod Soto, Chase Franklin Type: Hunting Product: Splunk Enterprise Security

Description

The following detection provides the ability to detect remote code execution attempts against a script named copybuckets present within the splunk_archiver application by calling this script as an external lookup.

1index=_internal sourcetype="splunk_archiver-too_small" *.csv 
2| rex field=_raw "Invoking command:\s(?<command>.*)" 
3| stats min(_time) as firstTime max(_time) as lastTime values(command) as command values(severity) as severity by host 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `splunk_rce_via_external_lookup_copybuckets_filter`

Data Source

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

Macros Used

Name Value
security_content_ctime convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)
splunk_rce_via_external_lookup_copybuckets_filter ``
splunk_rce_via_external_lookup_copybuckets_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
T1210 Exploitation of Remote Services Lateral Movement

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
Hunting detections do not generate a Finding (Notable) or Intermediate Findings (Risk Events).

Implementation

Requires access to internal indexes

Known False Positives

An operator must identify elements indicatives of command execution requests by looking at regex data being extracted from the log. Not all the requests will be malicious.

Associated Analytic Story

References

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

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: 5