Splunk Enterprise and Cloud Platform
CVE-2026-76258: Use of Hard-coded Cryptographic Key through Companion App Registration in Splunk Secure Gateway
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).
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Splunk Enterprise 10.4 | 10.4.2 or later |
| Splunk Enterprise 10.2 | 10.2.6 or later |
| Splunk Enterprise 10.0 | 10.0.9 or later |
| Splunk Enterprise 9.4 | 9.4.14 or later |
| Splunk Secure Gateway 3.10 | 3.10.10 or later |
| Splunk Secure Gateway 3.9 | 3.9.24 or later |
| Splunk Secure Gateway 3.8 | 3.8.71 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
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.
Workarounds
Upgrade Splunk Secure Gateway to versions 3.10.10, 3.9.24, and 3.8.71, or higher. If you are not able to upgrade Splunk Enterprise or Splunk Secure Gateway, turn off or remove the Splunk Secure Gateway app. See [Manage app and add-on objects](https://help.splunk.com/en/splunk-enterprise/administer/admin-manual/10.2/meet-splunk-apps/manage-app-and-add-on-objects) in the Splunk documentation. Note: Splunk Mobile, Spacebridge, and Mission Control rely on functionality in the Splunk Secure Gateway app. If you do not use any of these apps, features, or functionality, as a potential mitigation, you may turn off or remove the app.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.