CVE-2026-76313: Splunk Enterprise RCE Vulnerability

CVE-2026-76313 Overview

CVE-2026-76313 is a Remote Code Execution (RCE) vulnerability in Splunk Enterprise affecting distributed search deployments. The flaw allows a low-privileged authenticated user, who does not hold the admin or power Splunk role, to upload a malicious knowledge bundle. Distributed search then consumes that bundle on search peers, granting the attacker code execution and access to indexed data. The vulnerability is classified as Broken Access Control [CWE-284]. Splunk addressed the issue in Splunk Enterprise versions 10.4.2, 10.2.6, 10.0.9, and 9.4.14.

Critical Impact
An authenticated non-admin user can achieve code execution on Splunk search peers, compromising the confidentiality, integrity, and availability of all data indexed across the distributed search cluster.

Affected Products

Splunk Enterprise versions below 10.4.2 (10.4.x branch)
Splunk Enterprise versions below 10.2.6 and 10.0.9 (10.x branches)
Splunk Enterprise versions below 9.4.14 (9.4.x branch)

Discovery Timeline

2026-08-19 - CVE-2026-76313 published to NVD
2026-08-20 - Last updated in NVD database

Technical Details for CVE-2026-76313

Vulnerability Analysis

Splunk Enterprise uses knowledge bundle replication to distribute search-time configuration, lookups, and scripts from search heads to search peers (indexers). Any content packaged in a bundle can influence how peers process searches, including custom search commands and lookup scripts that execute on the peer.

The vulnerable Representational State Transfer (REST) API endpoint that accepts knowledge bundle uploads does not enforce the edit_dist_peer capability. Distributed search additionally accepts caller-supplied knowledge bundle selections from users lacking that capability. As a result, a low-privileged authenticated user can push a bundle containing attacker-controlled logic that is later evaluated by search peers, yielding Remote Code Execution.

Successful exploitation compromises every search peer that consumes the malicious bundle, exposing indexed data and enabling lateral movement within the Splunk cluster.

Root Cause

The root cause is a missing authorization check on the knowledge bundle upload REST endpoint. Splunk's role-based access control model reserves distributed search administration for capabilities such as edit_dist_peer, but the endpoint accepts bundle uploads and selections from any authenticated user. This is a Broken Access Control weakness [CWE-284].

Attack Vector

The attack vector is network-based and requires low-privilege authentication with no user interaction. An attacker with a standard Splunk account authenticates to the search head, submits a crafted knowledge bundle through the REST API, and instructs distributed search to distribute that bundle to peers. When peers execute searches against the bundle, attacker-controlled code runs in the Splunk process context.

No verified exploit code has been published. Refer to the Splunk Security Advisory SVD-2026-0801 for authoritative technical details.

Detection Methods for CVE-2026-76313

Indicators of Compromise

Unexpected knowledge bundle uploads by non-admin, non-power role users in splunkd_access.log targeting the bundle replication REST endpoints.
New or modified custom search commands, scripted lookups, or bin/ scripts appearing in replicated bundles on search peers.
Unusual child processes spawned by splunkd on search peers, particularly shell interpreters or network utilities.
REST API calls invoking distributed search bundle selection from accounts lacking the edit_dist_peer capability.

Detection Strategies

Baseline which accounts legitimately upload knowledge bundles and alert on deviations, especially uploads from accounts without administrative roles.
Monitor audit.log and splunkd_access.log for POST requests to knowledge bundle and distributed peer REST endpoints correlated with role information.
Inspect replicated bundle contents on search peers for unexpected executable payloads, commands.conf entries, or scripted lookup definitions.

Monitoring Recommendations

Forward Splunk internal logs (_internal index) to an independent monitoring platform so attackers who gain RCE on peers cannot fully erase evidence.
Alert on process creation events where splunkd or its search helpers spawn interpreters such as python, sh, bash, powershell.exe, or cmd.exe outside expected search workloads.
Track authentication events for standard-role accounts that suddenly interact with distributed search administration endpoints.

How to Mitigate CVE-2026-76313

Immediate Actions Required

Upgrade Splunk Enterprise to 10.4.2, 10.2.6, 10.0.9, 9.4.14, or later depending on the deployed branch.
Audit all non-admin, non-power accounts and revoke unnecessary access to search heads that participate in distributed search.
Rotate credentials and session tokens for any account that may have interacted with knowledge bundle endpoints prior to patching.
Review recent knowledge bundles distributed to search peers for unauthorized modifications.

Patch Information

Splunk released fixed versions in 10.4.2, 10.2.6, 10.0.9, and 9.4.14. The patched builds enforce the edit_dist_peer capability requirement on the knowledge bundle upload REST endpoint and reject caller-supplied bundle selections from users without that capability. Full remediation details are documented in the Splunk Security Advisory SVD-2026-0801.

Workarounds

Restrict network access to the search head REST API so only trusted administrators and services can reach knowledge bundle endpoints.
Remove or reduce role assignments for users who do not require search head access, and confirm the edit_dist_peer capability is granted only where required.
Monitor the _audit and _internal indexes for REST activity targeting distributed search endpoints until the patch is deployed.

bash

# Configuration example: verify installed Splunk version before and after patching
$SPLUNK_HOME/bin/splunk version

# Review role capabilities to confirm edit_dist_peer is scoped appropriately
$SPLUNK_HOME/bin/splunk list role admin
$SPLUNK_HOME/bin/splunk list role power