CVE-2026-76314: Splunk Enterprise RCE Vulnerability

CVE-2026-76314 Overview

CVE-2026-76314 is a remote code execution vulnerability in Splunk Enterprise. The flaw allows an authenticated low-privileged user, one without the admin or power roles, to execute arbitrary code by submitting crafted Splunk Web Manager configuration content. Splunk Web evaluates manager Extensible Markup Language (XML) expressions without sufficient input restrictions. The associated configuration route also fails to require the capability normally expected for manager configuration changes. Successful exploitation compromises confidentiality, integrity, and availability of the Splunk instance and any data it processes. The issue is tracked under CWE-94: Improper Control of Generation of Code.

Critical Impact
Authenticated low-privileged users can achieve full remote code execution on Splunk Enterprise, exposing all indexed data and enabling downstream compromise of connected systems.

Affected Products

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

Discovery Timeline

2026-08-19 - CVE-2026-76314 published to NVD
2026-08-20 - Last updated in NVD database

Technical Details for CVE-2026-76314

Vulnerability Analysis

CVE-2026-76314 is a code injection flaw in the Splunk Web management interface. Splunk Web accepts manager configuration content expressed as XML and evaluates embedded expressions on the server. The evaluation logic does not sufficiently restrict which expressions or referenced objects may be resolved. An authenticated user can therefore craft configuration content that causes the server to execute arbitrary code within the Splunk process context.

Exploitation grants access to all data the Splunk instance can read, including indexed logs and forwarded telemetry. Attackers can also modify configuration, disable auditing, or pivot to other systems that trust the Splunk deployment.

Root Cause

Two defects combine to produce the vulnerability. First, Splunk Web evaluates manager XML expressions without adequate input validation or expression allowlisting. Second, the HTTP route handling manager configuration changes does not enforce the capability check that normally restricts these operations to administrative roles. As a result, a non-admin, non-power user can reach the vulnerable evaluation path and inject executable content.

Attack Vector

The attack is delivered over the network to the Splunk Web interface. The attacker must hold valid credentials for any Splunk user account, including accounts with only default roles. No user interaction is required beyond the attacker's own authenticated session. The attacker submits a crafted request containing XML manager configuration content that includes a malicious expression, and Splunk Web evaluates it on the server.

Because AV:N/AC:L/PR:L/UI:N conditions apply, any environment that permits broad low-privilege account creation, self-service registration, or forwarder credential reuse is at elevated risk. See the Splunk Security Advisory SVD-2026-0801 for vendor-specific detail.

Detection Methods for CVE-2026-76314

Indicators of Compromise

Unexpected POST or PUT requests to Splunk Web manager configuration endpoints originating from non-administrative user sessions.
New or modified Splunk configuration files (.conf entries) written outside of change-management windows, particularly by low-privileged accounts.
Child processes spawned by the Splunk daemon (splunkd, splunkweb) that execute shell interpreters, scripting runtimes, or network utilities.
Outbound network connections from Splunk hosts to previously unseen external destinations following manager configuration activity.

Detection Strategies

Correlate Splunk _audit and _internal index events with process-execution telemetry from the underlying host to identify configuration changes followed by anomalous process creation.
Alert on any manager configuration modification performed by accounts that lack the admin or power role.
Deploy behavioral detections for XML payloads containing expression constructs submitted to /en-US/manager/ or equivalent management routes.

Monitoring Recommendations

Forward Splunk Web access logs and audit logs to an independent monitoring system so tampering by a compromised Splunk instance is detectable.
Baseline expected administrative activity per user role, and generate alerts on deviations, especially manager route requests from low-privileged accounts.
Monitor for unexpected changes to Splunk startup scripts, apps under $SPLUNK_HOME/etc/apps, and scheduled searches created by non-admin users.

How to Mitigate CVE-2026-76314

Immediate Actions Required

Upgrade Splunk Enterprise to version 10.4.2, 10.2.6, 10.0.9, or 9.4.14 or later, matching your maintenance track.
Audit all Splunk user accounts and remove or disable accounts that do not require interactive access, particularly stale forwarder or integration accounts.
Restrict network access to Splunk Web so that only trusted administrative networks can reach management endpoints.
Review recent manager configuration changes and audit logs for evidence of exploitation prior to patching.

Patch Information

Splunk has released fixed builds in the 10.4.2, 10.2.6, 10.0.9, and 9.4.14 maintenance releases. Refer to Splunk Security Advisory SVD-2026-0801 for build identifiers, download locations, and upgrade guidance. Apply the vendor patch as the primary remediation; configuration workarounds do not fully close the code evaluation path.

Workarounds

If immediate patching is not possible, disable Splunk Web on indexers and other non-UI nodes by setting startwebserver = 0 in web.conf.
Place Splunk Web behind an authenticating reverse proxy that enforces IP allowlisting for administrative routes.
Enforce strong password policies and multi-factor authentication on all Splunk accounts to reduce the pool of usable low-privileged credentials.

bash

# Disable Splunk Web on hosts where the UI is not required
# $SPLUNK_HOME/etc/system/local/web.conf
[settings]
startwebserver = 0

# Then restart Splunk
$SPLUNK_HOME/bin/splunk restart