CVE-2026-76258 MEDIUM

CVE-2026-76258: Use of Hard-coded Cryptographic Key through Companion App Registration in Splunk Secure Gateway

Vendor Splunk
Product Splunk Enterprise
Weakness CWE-321
Published August 19, 2026
Last update August 26, 2026

CVSS base score

6.5/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity None

CVSS vector

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

What the vulnerability does

01Description

In Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.14, and Splunk Secure Gateway versions below 3.10.10, 3.9.24, and 3.8.71, a user who does not hold the "admin" or "power" Splunk roles could register an arbitrary companion app and cause Splunk Secure Gateway to forward mobile user requests, including tokens that compromise all relevant data available to the affected mobile user, to an attacker-controlled Uniform Resource Locator (URL). The vulnerability is possible because a hard-coded cryptographic key in the Splunk Secure Gateway companion app registration handler allows for arbitrary callback URL registration without restriction. For more information see Define roles on the Splunk platform with capabilities (https://help.splunk.com/en/splunk-enterprise/administer/manage-users-and-security/10.2/manage-splunk-platform-users-and-roles/define-roles-on-the-splunk-platform-with-capabilities) in the Splunk documentation.

Key dates

02Disclosure timeline

August 19, 2026 CVE published
August 26, 2026 Record updated