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TI-2026-69310 Aliases CVE-2026-76286GHSA-mgwr-9j5x-6w4x

Server-side request forgery in Splunk MCP Server custom API tools

Priority LOW 23CWE-918Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
Required
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · Low · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Splunk MCP Server from 1.2 before 1.2.1 could send the Splunk platform authentication token of a user who runs a custom API tool to the URL configured for that tool. An attacker who controls that URL and can get a user holding the mcp_tool_execute capability to run the tool could capture the token and act as that user, with high confidentiality impact and limited integrity and availability impact. The flaw is a server-side request forgery (CWE-918).

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00174 6th percentileScored 2026-11-07
Fix Fixed Splunk MCP Server (Splunk): 1.2.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
SplunkSplunk MCP Server1.2 to before 1.2.11.2.1Patch availableCNA
  • Splunk MCP Server VendorSplunk Affected 1.2 to before 1.2.1 Fixed in 1.2.1 Patch available CNA

Remediation

Upgrade Splunk MCP Server to version 1.2.1. Splunk's advisory for this issue is not listed in the sources.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA Splunk MCP Server (Splunk) Fixed in 1.2.1

Timeline

  1. 2026-10-07 Threatist record created from CVE-2026-76286
  2. 2026-10-07 Alias added: GHSA-mgwr-9j5x-6w4x
  3. 2026-10-08 CISA SSVC decision points changed

References

Other 1

  • TI-2026-16444 Unauthenticated Arbitrary File Creation and Truncation in a PostgreSQL Sidecar Service Endpoint in Splunk Enterprise KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-00154 The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly… KEVCVSS 3.1HIGH 7.5
  • TI-2023-24841 Remote code execution (RCE) in Splunk Enterprise through Insecure XML Parsing CVSS 3.1HIGH 8.8
  • TI-2023-12257 Injection in https://github.com/curl/curl CVSS 3.1CRITICAL 9.8
  • TI-2022-13930 Information disclosure in https://github.com/curl/curl CVSS 3.1CRITICAL 9.8
  • TI-2022-13917 Incorrect default permissions in https://github.com/curl/curl CVSS 3.1CRITICAL 9.8
See all 450 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences