by Kastro
Paper/Archive/CVE-2026-76404

CVE-2026-76404

Splunk Splunk MCP Server app — Remote Code Execution (RCE) through Deserialization of Untrusted Data in Splunk MCP Server app

EPSS 0.7%CVSS 9.1
critical.is priorityof 100
38
CVSS 9.1 (CNA)9.1 / 10 × 3027.3Not in CISA KEV+300.0EPSS percentile 54.9.549 × 2011.0No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

In Splunk MCP Server app versions below 1.2.1, a user who holds the "admin" Splunk role could execute arbitrary commands on the underlying operating system. The vulnerability is possible because of missing input validation in the app's credential management component, which deserializes stored data without checking whether the content is of the expected type.

Affected

ProductAffectedFixed inSource
Splunk MCP Server app1.2 – < 1.2.11.2.1CNA

Scores by source

cisco (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

refadvisory.splunk.com/advisories/SVD-2026-0808