Auth bypass in Splunk

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.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.004 (29.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 29th percentile — 29.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-76340: held from 0.003 to 0.004.

EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-76340?
CVE-2026-76340 is a medium-severity vulnerability in Splunk, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-08-19.
How severe is CVE-2026-76340?
Medium severity. CVSS v3 base score is 5.3 out of 10.