CVE-2024-29946: Splunk Enterprise Auth Bypass Vulnerability

CVE-2024-29946 Overview

CVE-2024-29946 is a command injection vulnerability in Splunk Enterprise's Dashboard Examples Hub component. The vulnerability exists because the Dashboard Examples Hub lacks adequate protections for risky SPL (Search Processing Language) commands, allowing attackers to bypass established SPL safeguards. Successful exploitation requires social engineering, where an attacker must phish the victim into initiating a malicious request within their browser session.

Critical Impact

Attackers can bypass SPL command safeguards through the Dashboard Examples Hub, potentially leading to unauthorized access to sensitive data and system compromise via crafted phishing attacks.

Affected Products

• Splunk Enterprise versions below 9.2.1
• Splunk Enterprise versions below 9.1.4
• Splunk Enterprise versions below 9.0.9

Discovery Timeline

• 2024-03-27 - CVE-2024-29946 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2024-29946

Vulnerability Analysis

This vulnerability stems from insufficient input validation and improper neutralization of special elements used in command execution (CWE-77) within Splunk Enterprise's Dashboard Examples Hub. The Hub component fails to properly validate and sanitize SPL commands before execution, creating a pathway for attackers to inject malicious commands that bypass existing security controls designed to prevent dangerous SPL operations.

The attack requires user interaction, specifically through phishing techniques that trick authenticated Splunk users into triggering malicious requests. Once a victim initiates such a request from their browser, the attacker can leverage the vulnerability to execute risky SPL commands that would normally be blocked by Splunk's security safeguards. This can result in high-impact consequences to data confidentiality and integrity.

Root Cause

The root cause of CVE-2024-29946 lies in improper input validation (CWE-20) combined with command injection weaknesses (CWE-77) in the Dashboard Examples Hub. The component does not adequately enforce the same SPL command restrictions that exist elsewhere in Splunk Enterprise, creating an inconsistent security boundary that attackers can exploit.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker must craft a malicious request and use social engineering techniques to convince an authenticated Splunk Enterprise user to initiate that request from their browser. The attack flow typically involves:

1. Attacker identifies vulnerable Splunk Enterprise deployment running affected versions
2. Attacker crafts malicious SPL commands designed to bypass security controls
3. Attacker constructs a phishing payload that, when triggered by the victim, sends the malicious request to the Dashboard Examples Hub
4. Victim, already authenticated to Splunk Enterprise, clicks the phishing link or interacts with malicious content
5. The Dashboard Examples Hub processes the request without proper SPL command safeguards, executing the dangerous commands

The vulnerability mechanism involves the Dashboard Examples Hub processing SPL commands without the same protective measures applied to standard Splunk search interfaces. Attackers can exploit this gap by embedding risky SPL commands within requests that appear legitimate to the Hub component. For detailed technical information, refer to the Splunk Security Advisory SVD-2024-0302 and the Splunk Research Application Analysis.

Detection Methods for CVE-2024-29946

Indicators of Compromise

• Unusual SPL command execution patterns originating from the Dashboard Examples Hub
• Unexpected network requests to Splunk Enterprise from user browsers following potential phishing interactions
• Log entries showing risky SPL commands executed through non-standard pathways
• Evidence of phishing attempts targeting Splunk Enterprise users

Detection Strategies

• Monitor Splunk internal logs for SPL command execution through the Dashboard Examples Hub component
• Implement detection rules for anomalous SPL commands that bypass standard search interfaces
• Deploy email and web filtering to detect phishing attempts targeting Splunk users
• Use the detection content provided by Splunk Research to identify exploitation attempts

Monitoring Recommendations

• Enable enhanced audit logging for the Dashboard Examples Hub component
• Monitor for unusual user session activity following external link access
• Implement behavioral analytics to detect abnormal SPL command patterns
• Review Splunk access logs for requests originating from unexpected referrer URLs

How to Mitigate CVE-2024-29946

Immediate Actions Required

• Upgrade Splunk Enterprise to version 9.2.1, 9.1.4, or 9.0.9 or later based on your major version branch
• Restrict access to the Dashboard Examples Hub to only trusted administrators
• Implement additional phishing awareness training for Splunk Enterprise users
• Review and audit recent Dashboard Examples Hub activity for signs of exploitation

Patch Information

Splunk has released security patches addressing this vulnerability. Organizations should upgrade to the following fixed versions based on their current deployment:

• Version 9.2.x: Upgrade to 9.2.1 or later
• Version 9.1.x: Upgrade to 9.1.4 or later
• Version 9.0.x: Upgrade to 9.0.9 or later

For complete patch details and upgrade instructions, refer to the Splunk Security Advisory SVD-2024-0302.

Workarounds

• Disable or restrict access to the Dashboard Examples Hub if immediate patching is not feasible
• Implement network-level controls to limit external referrer-based requests to Splunk Enterprise
• Deploy web application firewall rules to filter potentially malicious SPL command patterns
• Enforce strict Content Security Policy headers to mitigate browser-based attack vectors

# Example: Restrict Dashboard Examples Hub access via Splunk configuration
# Add to authorize.conf to limit access to admin role only
[role_admin]
importRoles = user
srchFilter = *
srchIndexesAllowed = *
srchIndexesDefault = main
# Ensure only trusted roles have access to dashboard examples