CVE-2026-76278 in Splunk
Summary
by MITRE • 10/08/2026
In Splunk Enterprise versions below 10.4.3, 10.2.7, and 10.0.10, a user that holds a role with the edit_spl2_module_permissions capability could use the affected Representational State Transfer (REST) API to access permission grants for SPL2 modules that the user does not have permission to view. The vulnerability is possible because Splunk Enterprise does not verify that the user can read the requested app before the affected REST API returns SPL2 module permission grants. For more information see Module permissions (https://help.splunk.com/en/splunk-enterprise/search/spl2-search-manual/modules-statements-and-views/module-permissions) and Manage SPL2 modules (https://help.splunk.com/en/splunk-enterprise/search/spl2-search-manual/multiple-searches-in-an-spl2-module/manage-spl2-modules) in the Splunk documentation.
Splunk Enterprise versions 9.4.x are not affected.
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Analysis
by VulDB Data Team • 10/08/2026
The vulnerability identified in specific early releases of Splunk Enterprise, including versions prior to 10.4.3, 10.2.7, and 10.0.10, represents a critical failure in access control logic within the application's Representational State Transfer (REST) API infrastructure. This flaw specifically impacts users who have been assigned roles containing the edit_spl2_module_permissions capability. While this permission is intended to allow authorized personnel to modify module configurations, it inadvertently grants these users the ability to bypass standard authorization checks when querying SPL2 module permissions via a specific REST endpoint. The core technical deficiency lies in the server-side validation process, which fails to verify that the requesting user possesses read access to the underlying application or namespace associated with the requested SPL2 modules before returning sensitive permission grant data. This lack of cross-referencing between the edit capability and the fundamental read permissions creates a logic flaw where administrative privileges are exploited to enumerate security configurations beyond the scope of the user's intended visibility.
From an operational perspective, this vulnerability allows for unauthorized information disclosure regarding the internal structure and access controls of Splunk applications. By exploiting this API endpoint, an attacker or malicious insider can retrieve detailed permission grants for SPL2 modules that they should not be able to view. This exposure reveals which users or roles have specific rights to execute, modify, or manage certain search modules within restricted apps. Such information is highly valuable in the context of a broader attack campaign as it aids in mapping out the security posture of the environment. The attacker can identify high-value targets, understand privilege escalation paths, and potentially plan further exploitation attempts against other components that rely on these module permissions for their functionality. This aligns with common patterns observed in enterprise software where granular administrative capabilities are not sufficiently isolated from general enumeration functions.
The technical nature of this flaw is best classified under CWE-284, which describes Improper Access Control, specifically focusing on the failure to enforce proper restrictions on users regarding access to resources or functionality. The vulnerability enables an unauthorized actor to gain information about system configurations that should remain confidential based on their role-based permissions. In terms of offensive security frameworks, this behavior corresponds to ATT&CK technique T1087, Account Discovery, as it allows the enumeration of user roles and associated privileges within the Splunk environment. Furthermore, because the exploitation involves interacting with a web service API to extract data, it also falls under the broader category of API abuse often seen in modern application security assessments. The absence of a check for read permissions on the parent app before processing the request is a classic example of broken object level authorization principles being violated within an administrative interface.
Mitigation strategies must prioritize immediate patching and access control refinement. Splunk has addressed this issue in versions 10.4.3, 10.2.7, and 10.0.10, making the upgrade to one of these patched releases the primary remediation step for affected environments. Organizations running version 9.4.x are confirmed not to be susceptible to this specific vulnerability due to differences in their codebase or permission handling logic. For organizations unable to patch immediately, it is advisable to restrict access to the Splunk management interface through network segmentation and strict firewall rules, ensuring that only trusted administrative workstations can reach the REST API endpoints. Additionally, reviewing role definitions to ensure that the edit_spl2_module_permissions capability is granted only to a minimal set of highly privileged administrators who require such access can reduce the attack surface. Implementing Web Application Firewalls (WAFs) with rules designed to detect anomalous enumeration patterns against SPL2 module permission endpoints may also provide an additional layer of defense by blocking requests that exhibit characteristics of unauthorized data harvesting.