Description

In Splunk Enterprise versions below 10.4.2, a user with a high-privilege Splunk role that can manage search head clustering could use the search head cluster member bundle Representational State Transfer (REST) API to write files to locations that the user account running Splunk Enterprise can write to, which could allow for remote code execution. Successful exploitation could result in access to all relevant data and could affect the integrity and availability of the Splunk deployment. The vulnerability does not affect Splunk Enterprise versions below 10.4. The vulnerability is possible because the search head cluster member bundle REST API does not enforce the expected authorization boundary and does not validate bundle paths before accepting bundle content. For more information see Using the REST API reference (https://help.splunk.com/en/splunk-enterprise/rest-api-reference/10.2/introduction/using-the-rest-api-reference), About configuring role-based user access (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.2/manage-splunk-platform-users-and-roles/about-configuring-role-based-user-access), and About distributed search (https://help.splunk.com/en/splunk-enterprise/administer/distributed-search/9.4/overview-of-distributed-search/about-distributed-search) in the Splunk documentation.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.0",
  "pubDate": "2026-08-19T22:17:19.297Z",
  "pubdate": "2026-08-19T22:17:19.297Z",
  "executiveSummary": "A critical vulnerability exists in Splunk Enterprise allowing authenticated users with high-privilege roles to achieve remote code execution via arbitrary file write capabilities. The vulnerability affects Splunk Enterprise versions below 10.4.2 (specifically impacting versions starting from 10.4 where the vulnerable code was introduced). Successful exploitation requires a high-privilege Splunk role capable of managing search head clustering. An attacker possessing these elevated privileges can leverage the search head cluster member bundle Representational State Transfer (REST) API to write files to arbitrary locations accessible to the underlying operating system user account running the Splunk Enterprise service. This bypasses expected authorization boundaries and lacks proper validation of bundle paths before accepting bundle content. The impact of successful exploitation includes potential remote code execution on the underlying host, granting the adversary access to all relevant data and severely compromising the confidentiality, integrity, and availability of the entire Splunk deployment. Mitigation requires applying vendor-supplied updates or restricting high-privilege administrative access to trusted personnel.",
  "technicalDetails": "The vulnerability resides within the search head cluster member bundle Representational State Transfer (REST) API of Splunk Enterprise. Specifically, the root cause stems from an authorization boundary enforcement failure and a lack of proper input validation regarding bundle paths before the application accepts and processes bundle content. The vulnerable component is exposed through the search head cluster management REST API endpoints.\nExploitation of this vulnerability requires authentication and high-privilege user capabilities. An attacker must possess a high-privilege Splunk role that has explicit permissions to manage search head clustering. Network exposure includes access to the Splunk Enterprise REST API interface.\nThe step-by-step attack flow proceeds as follows: First, the authenticated attacker interacts with the search head cluster member bundle Representational State Transfer (REST) API. Second, the attacker crafts a malicious bundle payload containing arbitrary file write instructions directed at sensitive directories accessible by the OS user account executing the Splunk Enterprise process. Third, because the API fails to validate bundle paths and improperly enforces authorization boundaries regarding target file locations, the application accepts the malicious bundle content. Fourth, the Splunk Enterprise application writes the payload files to the specified filesystem locations. Finally, by overwriting or placing executable scripts or configuration files into critical system paths reachable by the service account, the attacker achieves remote code execution.\nPost-exploitation impact encompasses total system compromise. The execution of arbitrary code under the security context of the user account running Splunk Enterprise allows the adversary to access all indexed and raw data, manipulate deployment configurations, escalate privileges locally if system misconfigurations exist, and disrupt the availability of the Splunk deployment."
}