Detection: Splunk RCE via Splunk Secure Gateway Splunk Mobile alerts feature

Updated Date: 2024-05-16 ID: baa41f09-df48-4375-8991-520beea161be Author: Rod Soto Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic identifies potential exploitation attempts against the Splunk Secure Gateway App's Mobile Alerts feature in Splunk versions 9.0, 8.2.x, and 8.1.x. It detects suspicious activity by monitoring requests to the mobile alerts endpoint using specific URI paths and query parameters. This activity is significant because an authenticated user could exploit this vulnerability to execute arbitrary operating system commands remotely. If confirmed malicious, this could lead to unauthorized code execution, compromising the integrity and security of the Splunk environment.

1`splunkda` uri_path="/servicesNS/nobody/splunk_secure_gateway/storage/collections/data/mobile_alerts*" sort="notification.created_at:-1" 
2| table  clientip file host method uri_query sort 
3| `splunk_rce_via_splunk_secure_gateway__splunk_mobile_alerts_feature_filter`

Data Source

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

Macros Used

Name Value
splunkda index=_internal sourcetype=splunkd_access
splunk_rce_via_splunk_secure_gateway__splunk_mobile_alerts_feature_filter search *
splunk_rce_via_splunk_secure_gateway__splunk_mobile_alerts_feature_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
KillChainPhase.EXPLOITAITON
NistCategory.DE_AE
Cis18Value.CIS_10
APT28
Dragonfly
Earth Lusca
Ember Bear
FIN7
Fox Kitten
MuddyWater
Threat Group-3390
Tonto Team
Wizard Spider
menuPass

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

This search only applies if Splunk Mobile Gateway is deployed in the vulnerable Splunk versions.

Known False Positives

This detection does not require you to ingest any new data. The detection does require the ability to search the _internal index. Focus of this search is "uri_path=/servicesNS/nobody/splunk_secure_gateway/storage/collections/data/mobile_alerts*" which is the injection point.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Possible exploitation attempt from $clientip$ 81 90 90
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 ✅ Passing N/A N/A N/A
Unit ✅ Passing Dataset /opt/splunk/var/log/splunk/splunkd_access.log splunkd_access
Integration ✅ Passing Dataset /opt/splunk/var/log/splunk/splunkd_access.log splunkd_access

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