Detection: Splunk RCE PDFgen Render

REMOVED DETECTION

This detection has been removed from the Splunk Threat Research content library and is no longer maintained or supported.

Reason: Detection has been deprecated. The metadata along with the search are not accurately capturing the malicious activity.

Removed in version: 6.4.0

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

Description

This is a hunting search designed to find and discover exploitation attempts against Splunk pdfgen render endpoint which results in remote

1index=_internal sourcetype=splunk_pdfgen _raw IN ("*base64*", "*lambda*", "*system*") 
2| stats count min(_time) as firstTime max(_time) as lastTime by index, sourcetype, host, _raw 
3| `security_content_ctime(firstTime)` 
4| `security_content_ctime(lastTime)` 
5| `splunk_rce_pdfgen_render_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_pdfgen_render_filter ``
splunk_rce_pdfgen_render_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

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
TTP detections generate a Finding (Notable) and may generate Intermediate Findings (Risk Events) for associated entities.

Implementation

Requires access to internal indexes.

Known False Positives

This search will hunt for exploitation attempts against Splunk PDFgen render function, and not all requests are necesarily malicious so there will be false positives.

Associated Analytic Story

No 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
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: 8