CVE-2026-76258Use of Hard-coded Cryptographic Key through Companion App Registration in Splunk Secure Gateway
- 6.5MediumCVSS base score
- 0.34%Exploitation in 30 daysEPSS · top 72% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
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.
Timeline
ID reserved
By cisco
Published
- 7 days later
· 7 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
| NVDNVD · Analyzed | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.34% · top 72% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Affected products
- affected 10.4 – < 10.4.2
- affected 10.2 – < 10.2.6
- affected 10.0 – < 10.0.9
- affected 9.4 – < 9.4.14
Splunk · Splunk Secure Gateway
- affected 3.10 – < 3.10.10
- affected 3.9 – < 3.9.24
- affected 3.8 – < 3.8.71
What to do
Solution: Upgrade Splunk Enterprise to versions 10.4.2, 10.2.6, 10.0.9, and 9.4.14, or higher.
Workaround: 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.
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-63110 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-76258)Record last updated .