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

> CVE-2026-76258: Use of Hard-coded Cryptographic Key through Companion App Registration in Splunk Secure Gateway. CVSS 6.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-76258
Last updated: 2026-08-26T16:16:38Z

- Published: 2026-08-19 21:34 UTC · Updated: 2026-08-26 16:16 UTC · Assigner: cisco
- CVSS: 6.5 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- EPSS: 0.34%, 27th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-321

## Description

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.

## Affected vendors and products

- Splunk: Splunk Enterprise
- Splunk: Splunk Secure Gateway

## Tracked companies

- [Splunk](https://rewindex.com/company/splunk.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-76258)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-76258)
- [https://advisory.splunk.com/advisories/SVD-2026-0801](https://advisory.splunk.com/advisories/SVD-2026-0801)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-76258 · Markdown: https://rewindex.com/cve/CVE-2026-76258.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-76258 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:09:09.283Z