9.1

CVE-2026-76404: splunk model_context_protocol_server Deserialization of Untrusted Data

CVSS: 9.1v3.1CriticalAnalyzed
Published 19-08-2026Last modified 20-08-2026
Open JSON

Vulnerability summary

CVE-2026-76404 is a critical (CVSS 9.1) Deserialization of Untrusted Data vulnerability in splunk model_context_protocol_server. EPSS estimates a 0.75% chance of exploitation in the next 30 days, higher than 54% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.75%
0%100%
Low · +0.19 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 19-08-2026
    PublishedVulnerability first disclosed.
  2. 20-08-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.75%

Chance of exploitation in the next 30 days

Percentile

54%

Versus all other CVEs

30-day change

+0.19 pp

From 0.56% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.75%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Splunk2 products

1 vendor · 2 products

References

1 links