CVE-2026-76404 (GCVE-0-2026-76404)

Vulnerability from cvelistv5 – Published: 2026-08-19 21:35 – Updated: 2026-08-20 15:26
VLAI
Title
Remote Code Execution (RCE) through Deserialization of Untrusted Data in Splunk MCP Server app
Summary
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.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-20 15:09 UTC
CWE
  • CWE-502 - The application deserializes untrusted data without sufficiently verifying that the resulting data will be valid.
Assigner
References
Impacted products
Vendor Product Version CPE status
Splunk Splunk MCP Server app Affected: 1.2 , < 1.2.1 (custom)
guessed Create a notification for this product.
Date Public
2026-08-19 00:00
Credits
Kuniyoshi Noguchi (KuniNogu)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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