Server-Side Request Forgery (SSRF) through Custom API Tools in Splunk MCP Server
Summary
| CVE | CVE-2026-76286 |
|---|---|
| State | PUBLISHED |
| Assigner | cisco |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-07 21:17:20 UTC |
| Updated | 2026-10-08 20:08:45 UTC |
| Description | In Splunk MCP Server versions below 1.2.1, Splunk MCP Server could send the Splunk platform authentication token of a user who runs a custom Application Programming Interface (API) tool to the URL configured for that tool. If another user controls that URL, they could capture the token and use it to access data and perform actions as the user who ran the tool. Successful exploitation requires a user who holds a role that contains the mcp_tool_execute capability to run a custom API tool configured by another user. For more information see Configure the Splunk MCP Server (https://help.splunk.com/en/splunk-enterprise/mcp-server-for-splunk-platform/1.2/configure-the-splunk-mcp-server) and Managing custom tools in Splunk MCP Server (https://help.splunk.com/en/splunk-enterprise/mcp-server-for-splunk-platform/1.2/managing-custom-tools-in-splunk-mcp-server) in the Splunk documentation. |
Risk And Classification
Primary CVSS: v3.1 5.3 MEDIUM from [email protected]
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:L/A:L
EPSS: 0.001740000 probability, percentile 0.062690000 (date 2026-10-09)
Problem Types: CWE-918 | CWE-918 The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 5.3 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:L/A:L |
| 3.1 | CNA | CVSS | 5.3 | MEDIUM | CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:L/A:L |
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:L/A:L
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Splunk | Splunk MCP Server | affected 1.2 1.2.1 custom | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| advisory.splunk.com/advisories/SVD-2026-1004 | [email protected] | advisory.splunk.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Kuniyoshi Noguchi (KuniNogu) (en)
Additional Advisory Data
Solutions
CNA: Upgrade Splunk MCP Server to version 1.2.1 or higher.
Workarounds
CNA: Turn off or remove the Splunk MCP Server app. For more information see [Manage app and add-on objects](https://help.splunk.com/en/splunk-enterprise/administer/admin-manual/10.2/meet-splunk-apps/manage-app-and-add-on-objects) in the Splunk documentation.