Detection: Splunk Persistent XSS Via URL Validation Bypass W Dashboard

Updated Date: 2024-05-20 ID: 8a43558f-a53c-4ee4-86c1-30b1e8ef3606 Author: Rod Soto Type: Hunting Product: Splunk Enterprise Security

Description

The following analytic detects attempts to bypass URL validation in Splunk Enterprise versions below 9.0.4, 8.2.10, and 8.1.13 by targeting the vulnerable bootstrap version 2.3.1. It leverages splunkd_web logs, specifically monitoring GET requests to JavaScript files within the vulnerable bootstrap path. This activity is significant as it can allow a low-privileged user to perform path traversal, potentially accessing restricted and confidential information. If confirmed malicious, this could lead to unauthorized data access and compromise of sensitive information, including targeting admin users.

1`splunkd_web` method=GET uri_path="*bootstrap-2.3.1*" file="*.js" 
2| table _time clientip uri_path file status 
3| `splunk_persistent_xss_via_url_validation_bypass_w_dashboard_filter`

Data Source

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

Macros Used

Name Value
splunkd_web index=_internal sourcetype=splunk_web_access
splunk_persistent_xss_via_url_validation_bypass_w_dashboard_filter search *
splunk_persistent_xss_via_url_validation_bypass_w_dashboard_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 search does not require additional data to be ingested. This search requires ability to search _internal index. This search helps discover access to vulnerable bootstrap versions.

Known False Positives

This search will produce numerous false positives as it shows ANY accesses to vulnerable bootstrap Javascript files. Accesses to these files occur during normal Splunk usage. To reduce or eliminate false positives, update the a version of Splunk which has addressed the vulnerability.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message Risk Score Impact Confidence
Attempted access to vulnerable bootstrap file by $clientip$ 16 80 20
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/web_access.log splunk_web_access
Integration ✅ Passing Dataset /opt/splunk/var/log/splunk/web_access.log splunk_web_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