CVE-2026-76258: splunk Use of Hard-coded Cryptographic Key

Vulnerability summary

CVE-2026-76258 is a medium (CVSS 6.5) Use of Hard-coded Cryptographic Key vulnerability in splunk. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 26.2% of scored vulnerabilities.

Timeline

1. 19-08-2026
   PublishedVulnerability first disclosed.
2. 26-08-2026
   Last modifiedVulnerability information updated.

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.

• CWE-321Use of Hard-coded Cryptographic KeyThe product uses a hard-coded, unchangeable cryptographic key.