Detection: Splunk XSS via View

Updated Date: 2024-05-13 ID: 9ac2bfea-a234-4a18-9d37-6d747e85c2e4 Author: Rod Soto, Eric McGinnis, Splunk Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic identifies potential Cross-Site Scripting (XSS) attempts via the 'layoutPanel' attribute in the 'module' tag within XML Views in Splunk Enterprise versions below 8.1.13, 8.2.10, and 9.0.4. It leverages internal logs from "splunk_web_service" and "splunk_python" sourcetypes, focusing on messages containing "loadParams." This activity is significant as it can lead to unauthorized script execution within the Splunk Web interface, potentially compromising the security of the instance. If confirmed malicious, attackers could execute arbitrary scripts, leading to data theft, session hijacking, or further exploitation of the Splunk environment.

Search

1index = _internal sourcetype IN ("splunk_web_service", "splunk_python") message="*loadParams*" 
2| `security_content_ctime(_time)` 
3|  table _time message fileName 
4| `splunk_xss_via_view_filter`

Data Source

Name	Platform	Sourcetype	Source	Supported App
Splunk	Splunk	`'splunkd_ui_access'`	`'splunkd_ui_access.log'`	N/A

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
splunk_xss_via_view_filter	`search *`

splunk_xss_via_view_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

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

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 data is collected by default in Splunk. Upon first enabling this rule, a number of errors may be observed. Those that are due to improperly formatted, but non-nefarious, XML views should be be remedied in the corresponding view. Please take care investigating potential XSS as accessing an affected page could retrigger the exploit.

Known False Positives

The error detected above can be generated for a wide variety of improperly formatted XML views. There will be false positives as the search cannot extract the malicious payload and the view should be manually investigated.

Associated Analytic Story

Splunk Vulnerabilities

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
Potential stored XSS attempt via $fileName$	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

https://www.splunk.com/en_us/product-security.html

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`/opt/splunk/var/log/splunk/web_service.log`	`splunk_web_service`
Integration	✅ Passing	Dataset	`/opt/splunk/var/log/splunk/web_service.log`	`splunk_web_service`

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