Medium severity · published Aug 19, 2026
CVE-2026-76258
Use of Hard-coded Cryptographic Key through Companion App Registration in Splunk Secure Gateway
6.5
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 27% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SE
Splunk Enterprise · Splunk
10.4 before 10.4.2; 10.2 before 10.2.6; 10.0 before 10.0.9; 9.4 before 9.4.14 · source: vendor
SS
Splunk Secure Gateway · Splunk
3.10 before 3.10.10; 3.9 before 3.9.24; 3.8 before 3.8.71 · source: vendor, NVD
SP
Splunk · Splunk
9.4.0 before 9.4.14; 10.0.0 before 10.0.9; 10.2.0 before 10.2.6; 10.4.0 before 10.4.2 · source: NVD
Affected product
SE
Splunk Enterprise
Splunk
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