CVE-2025-20389 Improper Input Validation in "label" column field in Splunk Secure Gateway App

What is CVE-2025-20389?

CVE-2025-20389 is a medium-severity denial of service vulnerability in Splunk Splunk, published on 3 Dec 2025. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

In Splunk Enterprise versions below 10.0.2, 9.4.6, 9.3.8, and 9.2.10, and versions below 3.9.10, 3.8.58 and 3.7.28 of the Splunk Secure Gateway app on Splunk Cloud Platform, a low-privileged user that does not hold the "admin" or "power" Splunk roles could craft a malicious payload through the `label` column field after adding a new device in the Splunk Secure Gateway app. This could potentially lead to a client-side denial of service (DoS).

Weakness: CWE-20

Which versions are affected by CVE-2025-20389?

It affects 3 products.

Products include Splunk Splunk, Splunk Splunk Cloud Platform, Splunk Splunk Secure Gateway.

How do I fix CVE-2025-20389?

No fix has been published for CVE-2025-20389 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2025-20389 being exploited?

There is no known exploitation of CVE-2025-20389 in the wild and no public exploit code.

Other vulnerabilities in Splunk Splunk

• CVE-2026-20253 Splunk Enterprise Missing Authentication for Critical Function Exploited Critical 9.8
• CVE-2026-76268 Missing Authentication for Critical Function in the Patroni REST API in Splunk Enterprise Critical 9.8
• CVE-2026-76284 Improper Neutralization in Splunk Enterprise Critical 9.8
• CVE-2026-76285 Improper Adherence to Coding Standards in Splunk Enterprise Critical 9.8
• CVE-2017-17067 Auth bypass in n/a Critical 9.8

All Splunk Splunk vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-49x5-pp3j-h44f.