CVE-2026-23904: Apache Kyuubi: Unrestricted access via Kyuubi engine-ui proxy

Severity: high (CVSS 7.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-29 · updated 2026-10-23
Weakness: CWE-923

Description

Kyuubi Engine UI proxy accepts a host and port from the request path and proxies HTTP requests to that destination. A remote requester with network access to the proxy can cause the Kyuubi server to send HTTP requests to arbitrary reachable hosts, resulting in SSRF or open-proxy behavior. This issue affects Apache Kyuubi: from 1.8.0 before 1.12.0. Users are recommended to upgrade to version 1.12.0, which disables the proxy by default. To restore proxied Engine UI, set kyuubi.frontend.rest.engine.ui.proxy.enabled=true and configure allowed target hosts with kyuubi.frontend.rest.engine.ui.proxy.hosts.

Affected products

Apache Software Foundation Apache Kyuubi: from 1.8.0 before 1.12.0 — fixed in 1.12.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache Kyuubi 1.12.0. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-23904 or the next vulnerability affects your stack