CVE-2025-20378 Open Redirect on Web Login endpoint in Splunk Enterprise
An unauthenticated attacker can trick users into visiting malicious external sites via crafted login URLs in Splunk Enterprise.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-20378?
CVE-2025-20378 is a low-severity vulnerability in Splunk Splunk, published on 12 Nov 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-601
Which versions are affected by CVE-2025-20378?
It affects 2 products.
Products include Splunk Splunk, Splunk Splunk Cloud Platform.
How do I fix CVE-2025-20378?
No fix has been published for CVE-2025-20378 yet. Limit exposure of the affected software until one is available.
Is CVE-2025-20378 being exploited?
There is no known exploitation of CVE-2025-20378 in the wild and no public exploit code.
Other vulnerabilities in Splunk Splunk
- CVE-2026-20253 Splunk Enterprise Missing Authentication for Critical Function
- CVE-2026-76268 Missing Authentication for Critical Function in the Patroni REST API in Splunk Enterprise
- CVE-2026-76284 Improper Neutralization in Splunk Enterprise
- CVE-2026-76285 Improper Adherence to Coding Standards in Splunk Enterprise
- CVE-2017-17067 Auth bypass in n/a
Sources
Also known as GHSA-r9qj-q2g9-r74r.