CVE-2026-62391: Apache Kyuubi: kyuubi.session.local.dir.allow.list bypass via unprefixed Spark file-conf aliases

[Akira Ajisaka <aajisaka () apache org>]

Severity: important 

Affected versions:

- Apache Kyuubi (org.apache.kyuubi:kyuubi-server) 1.6.0 before 1.12.0

Description:

The security fix for CVE-2025-66518 is incomplete. Any client who can access to Apache Kyuubi Server via Kyuubi 
frontend protocols can bypass server-side config kyuubi.session.local.dir.allowlist via unprefixed Spark config aliases.

This issue affects Apache Kyuubi: from 1.6.0 before 1.12.0.

Users are recommended to upgrade to version 1.12.0, which fixes the issue.

Credit:

Anand Nalya (finder)

References:

https://kyuubi.apache.org
https://www.cve.org/CVERecord?id=CVE-2026-62391