CVE-2026-76258 (GCVE-0-2026-76258)

Vulnerability from cvelistv5 – Published: 2026-08-19 21:34 – Updated: 2026-08-26 15:23
VLAI
Title
Use of Hard-coded Cryptographic Key through Companion App Registration in Splunk Secure Gateway
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-26 14:49 UTC
CWE
  • CWE-321 - The use of a hard-coded cryptographic key significantly increases the possibility that encrypted data may be recovered.
Assigner
References
Impacted products
Vendor Product Version CPE status
Splunk Splunk Enterprise Affected: 10.4 , < 10.4.2 (custom)
Affected: 10.2 , < 10.2.6 (custom)
Affected: 10.0 , < 10.0.9 (custom)
Affected: 9.4 , < 9.4.14 (custom)
guessed Create a notification for this product.
Splunk Splunk Secure Gateway Affected: 3.10 , < 3.10.10 (custom)
Affected: 3.9 , < 3.9.24 (custom)
Affected: 3.8 , < 3.8.71 (custom)
guessed Create a notification for this product.
Date Public
2026-08-19 00:00
Credits
Gabriel Nitu, Splunk
Show details on NVD website
To clipboard 

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  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.