Splunk Enterprise and Cloud Platform
CVE-2025-20378: Open Redirect on Web Login endpoint in Splunk Enterprise
In Splunk Enterprise versions below 10.0.1, 9.4.5, 9.3.7, 9.2.9, and Splunk Cloud Platform versions below 10.0.2503.5, 9.3.2411.111, and 9.3.2408.121, an unauthenticated attacker could craft a malicious URL using the `return_to` parameter of the Splunk Web login endpoint.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Splunk Enterprise 10.0 | 10.0.1 or later |
| Splunk Enterprise 9.4 | 9.4.5 or later |
| Splunk Enterprise 9.3 | 9.3.7 or later |
| Splunk Enterprise 9.2 | 9.2.9 or later |
| Splunk Cloud Platform 10.0 | 10.0.2503.5 or later |
| Splunk Cloud Platform 9.3 | 9.3.2411.111 or later |
| Splunk Cloud Platform 9.3 | 9.3.2408.121 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
In Splunk Enterprise versions below 10.0.1, 9.4.5, 9.3.7, 9.2.9, and Splunk Cloud Platform versions below 10.0.2503.5, 9.3.2411.111, and 9.3.2408.121, an unauthenticated attacker could craft a malicious URL using the `return_to` parameter of the Splunk Web login endpoint. When an authenticated user visits the malicious URL, it could cause an unvalidated redirect to an external malicious site. To be successful, the attacker has to trick the victim into initiating a request from their browser. The unauthenticated attacker should not be able to exploit the vulnerability at will.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.