Detection: Splunk Persistent XSS via Scheduled Views

Updated Date: 2024-10-14 ID: d4f55f7c-6518-4122-a197-951fe0f21b25 Author: Rod Soto Type: Hunting Product: Splunk Enterprise Security

Description

In Splunk Enterprise versions below 9.2.3 and 9.1.6 and Splunk Cloud Platform versions below 9.1.2308.211, a low-privileged user that does not hold the “admin” or “power” Splunk roles could craft a malicious payload through Scheduled Views that could result in execution of unauthorized JavaScript code in the browser of a user.

Search

1`splunkd_ui` method=POST uri=*/scheduledview/search/update* 
2
3| stats  count earliest(_time) as firstTime  latest(_time) as lastTime values(bytes) AS bytes values(uri) AS uri values(useragent) AS user_agent by clientip user host
4
5| `security_content_ctime(firstTime)`
6
7| `security_content_ctime(lastTime)`
8
9| `splunk_persistent_xss_via_scheduled_views_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_persistent_xss_via_scheduled_views_filter	`search *`

splunk_persistent_xss_via_scheduled_views_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

Requires access to REST API.

Known False Positives

This is a hunting search, it is not possible to detect XSS payload from the scheduled view, however it is possible to see who was sent the scheduled search in order to trigger potential XSS.

Associated Analytic Story

Splunk Vulnerabilities

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
Possible XSS against $host$ please investigate further	10	20	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://advisory.splunk.com/advisories/SVD-2024-1010

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	N/A	`N/A`	`N/A`
Integration	✅ Passing	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: 1