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

[Akira Ajisaka <aajisaka () apache org>]

Severity: moderate 

Affected versions:

- Apache Kyuubi (org.apache.kyuubi:kyuubi-server) 1.8.0 before 1.12.0

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.

Credit:

Ícaro Torres (reporter)

References:

https://github.com/apache/kyuubi/pull/7483
https://kyuubi.apache.org
https://www.cve.org/CVERecord?id=CVE-2026-23904