CVE-2026-76340: splunk Auth Bypass — Fix

Description

In Splunk Enterprise 10.4 versions below 10.4.2, an unauthenticated user could cause Splunk Enterprise to reload token-signing keys through the Representational State Transfer (REST) API. The vulnerability does not affect Splunk Enterprise versions below 10.4. The vulnerability is possible because the REST API does not require authentication or the change_authentication capability for the token-key reload action. For more information see Define roles on the Splunk platform with capabilities (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/manage-splunk-platform-users-and-roles/define-roles-on-the-splunk-platform-with-capabilities) in the Splunk documentation.

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CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

EPSS — Exploit Prediction

0.0027

Probability of exploitation

0.19%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-862 Missing Authorization

Affected Products

Vendor	Product	Versions
splunk	splunk	10.4.0 — 10.4.2

References

Advisories & Patches

https://advisory.splunk.com/advisories/SVD-2026-0801

Frequently Asked Questions

What is CVE-2026-76340? +

In Splunk Enterprise 10.4 versions below 10.4.2, an unauthenticated user could cause Splunk Enterprise to reload token-signing keys through the Representational State Transfer (REST) API. The vulnerability does not affect Splunk Enterprise versions below 10.4. The vulnerability is possible because the REST API does not require authentication or the change_authentication capability for the token-key reload action. For more information see Define roles on the Splunk platform with capabilities (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.4/manage-splunk-platform-users-and-roles/define-roles-on-the-splunk-platform-with-capabilities) in the Splunk documentation. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2026-76340? +

CVE-2026-76340 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0027, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-76340? +

CVE-2026-76340 affects products from splunk, specifically: splunk. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-76340? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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