ID | Technique | Tactic |
---|---|---|
T1499.004 | Application or System Exploitation | Impact |
Detection: Splunk DOS Via Dump SPL Command
Description
The following analytic identifies a potential Denial of Service (DoS) attack exploiting the dump SPL command in vulnerable Splunk Enterprise versions. It detects this activity by searching the splunk_crash_log
for segmentation fault entries, indicating a crash of the Splunk daemon. This activity is significant for a SOC because it can disrupt the availability of Splunk services, impacting monitoring and incident response capabilities. If confirmed malicious, this attack could render Splunk Enterprise unusable, severely hindering an organization's ability to detect and respond to other security threats.
Search
1`splunk_crash_log` "*Segmentation fault*"
2| stats count by host _time
3| `splunk_dos_via_dump_spl_command_filter`
Data Source
Name | Platform | Sourcetype | Source | Supported App |
---|---|---|---|---|
Splunk | Splunk | 'splunkd_ui_access' |
'splunkd_ui_access.log' |
N/A |
Macros Used
Name | Value |
---|---|
splunk_crash_log | (index=_internal AND sourcetype=splunkd_crash_log) |
splunk_dos_via_dump_spl_command_filter | search * |
splunk_dos_via_dump_spl_command_filter
is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.
Annotations
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 |
Implementation
This search does not require additional ingestion of data. Requires the ability to search _internal index and monitor segmentation faults.
Known False Positives
Segmentation faults may occur due to other causes, so this search may produce false positives
Associated Analytic Story
Risk Based Analytics (RBA)
Risk Message | Risk Score | Impact | Confidence |
---|---|---|---|
Possible denial of service attack with Victim $host$ | 100 | 100 | 100 |
References
Detection Testing
Test Type | Status | Dataset | Source | Sourcetype |
---|---|---|---|---|
Validation | ✅ Passing | N/A | N/A | N/A |
Unit | ✅ Passing | Dataset | /opt/splunk/var/log/splunk/splunkd.log |
splunkd_crash_log |
Integration | ✅ Passing | Dataset | /opt/splunk/var/log/splunk/splunkd.log |
splunkd_crash_log |
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: 2