CVE-2025-20378

CVE-2025-20378 is a low-severity vulnerability in Splunk with a CVSS 3.x base score of 3.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-601.

Key facts

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.

Frequently asked questions

What is CVE-2025-20378?
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.
How severe is CVE-2025-20378?
CVE-2025-20378 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2025-20378 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-20378?
CVE-2025-20378 primarily affects Splunk. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-20378?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-20378 have an EU (EUVD) identifier?
Yes. CVE-2025-20378 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-131961.
When was CVE-2025-20378 published?
CVE-2025-20378 was published on 2025-11-12 and last updated on 2026-06-17.

References

Affected products (3)

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