Open Redirect CVE-2025-20378

This vulnerability is classified as Open Redirect (CWE-601), which allows attackers to redirect users to malicious websites via URL manipulation. 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. Affected products include: Splunk, Splunk Splunk Cloud Platform.