CVE-2026-76315: Splunk Enterprise RCE Vulnerability

CVE-2026-76315 Overview

CVE-2026-76315 is a code injection vulnerability [CWE-94] in Splunk Enterprise that allows a low-privileged authenticated user to execute arbitrary code on the Splunk platform instance. The flaw resides in Splunk Web Manager Configuration, which evaluates manager configuration values without enforcing the permission that normally controls manager configuration writes.

Affected releases include Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.14. A user without the admin or power role can leverage the Representational State Transfer (REST) API path for manager configuration to reach the vulnerable evaluation logic.

Critical Impact
A low-privileged Splunk user can execute arbitrary code, access all indexed data, and compromise the integrity and availability of the Splunk platform instance.

Affected Products

Splunk Enterprise versions below 10.4.2
Splunk Enterprise versions below 10.2.6
Splunk Enterprise versions below 10.0.9 and 9.4.14

Discovery Timeline

2026-08-19 - CVE-2026-76315 published to NVD
2026-08-20 - Last updated in NVD database

Technical Details for CVE-2026-76315

Vulnerability Analysis

The vulnerability exists in Splunk Web Manager Configuration, a component that processes manager configuration values used by the Splunk platform. The Web Manager evaluates these configuration values during processing, which enables code injection when an attacker controls the input. Because the affected REST API endpoint does not enforce the permission that normally guards manager configuration writes, authenticated users without the admin or power roles can reach the vulnerable code path.

Successful exploitation gives the attacker code execution in the context of the Splunk platform instance. From that position, the attacker can read every index and configuration on the instance, tamper with search results and dashboards, and disrupt data ingestion. Splunk addressed the issue in versions 10.4.2, 10.2.6, 10.0.9, and 9.4.14 per Splunk Security Advisory SVD-2026-0801.

Root Cause

Two defects combine to produce the vulnerability. First, Splunk Web Manager Configuration evaluates manager configuration values instead of treating them as opaque data, meeting the definition of [CWE-94] Improper Control of Generation of Code. Second, the REST API path exposing manager configuration writes does not require the role-based permission that normally governs those writes, which weakens the intended role-based access control model documented in restmap.conf.

Attack Vector

The attack vector is network-based and requires an authenticated Splunk account without elevated roles. An attacker submits a crafted request to the manager configuration REST API endpoint. The endpoint processes the request without checking the permission that ordinarily restricts manager configuration writes. The submitted value is evaluated by Splunk Web Manager Configuration, resulting in arbitrary code execution on the Splunk platform instance.

The vulnerability manifests in the manager configuration REST handler. See Splunk Security Advisory SVD-2026-0801 for vendor-authored technical details.

Detection Methods for CVE-2026-76315

Indicators of Compromise

Unexpected authenticated requests to manager configuration REST endpoints from accounts lacking admin or power roles.
New or modified .conf files, scripted inputs, or app bundles on Splunk instances that do not correspond to change tickets.
Splunk processes spawning shells, python, or other interpreters outside normal search execution paths.
Outbound network connections initiated by the splunkd service to previously unseen destinations.

Detection Strategies

Audit _audit and _internal indexes for REST calls to manager configuration paths issued by users without administrative roles.
Correlate REST activity with subsequent process creation events on Splunk hosts to surface post-exploitation execution.
Alert on modifications to restmap.conf, authorize.conf, and role definitions that follow suspicious authenticated sessions.

Monitoring Recommendations

Forward Splunk audit logs and host process telemetry to a central analytics platform for cross-source correlation.
Track authentication and role assignments for signs of privilege changes preceding manager configuration API use.
Baseline normal REST API traffic per user and role, and alert on deviations targeting configuration endpoints.

How to Mitigate CVE-2026-76315

Immediate Actions Required

Upgrade Splunk Enterprise to 10.4.2, 10.2.6, 10.0.9, 9.4.14, or later as specified in the vendor advisory.
Review all non-administrative Splunk accounts and revoke unnecessary access to Splunk Web and REST endpoints.
Rotate credentials, tokens, and secrets stored on any Splunk instance suspected of exposure.
Inspect installed apps and configurations for unauthorized changes introduced through the manager configuration path.

Patch Information

Splunk released fixed versions 10.4.2, 10.2.6, 10.0.9, and 9.4.14. Refer to Splunk Security Advisory SVD-2026-0801 for the authoritative fix list and upgrade guidance.

Workarounds

Restrict network access to Splunk Web and the management REST port so that only trusted administrative networks can reach them.
Remove or downgrade Splunk role assignments that grant access to Splunk Web for users who do not require it.
Disable Splunk Web on indexers and other components where the management UI is not required for operations.

bash

# Configuration example: restrict Splunk Web and management port access
# server.conf
[general]
# Disable Splunk Web on nodes that do not need it

# web.conf
[settings]
startwebserver = 0

# Limit management REST access with host-based firewalling (example: iptables)
iptables -A INPUT -p tcp --dport 8089 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 8089 -j DROP