CVE-2026-76252 PUBLISHED

Cross-Site Scripting (XSS) through Splunk Web Message Validation in Splunk Enterprise

Assigner: cisco
Reserved: 19.08.2026 Published: 19.08.2026 Updated: 19.08.2026

In Splunk Enterprise versions below 10.4.2, 10.2.6, 10.0.9, and 9.4.13, an unauthenticated user who tricks another user into visiting a malicious web page could run unauthorized JavaScript in that user's browser. This could allow for unauthorized access to all relevant data available to that user and actions that affect system integrity. The Cross-Site Scripting (XSS) is possible because Splunk Web does not validate the origin and source of messages received by a page message handler. The vulnerability requires the attacker to phish the affected user by tricking them into initiating a request within their browser. The unauthenticated user should not be able to exploit the vulnerability at will.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
CVSS Score: 6.8

Product Status

Vendor Splunk
Product Splunk Enterprise
Versions
  • affected from 10.4 to 10.4.2 (excl.)
  • affected from 10.2 to 10.2.6 (excl.)
  • affected from 10.0 to 10.0.9 (excl.)
  • affected from 9.4 to 9.4.13 (excl.)

Workarounds

The vulnerability affects instances with Splunk Web turned on. Turning Splunk Web off is a possible workaround. See Disable unnecessary Splunk Enterprise components and the web.conf configuration specification file for more information on turning off Splunk Web.

Solutions

Upgrade Splunk Enterprise to versions 10.4.2, 10.2.6, 10.0.9, and 9.4.14, or higher.

References

Problem Types

  • The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. cwe