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

> Attackers can bypass local directory allowlist restrictions in Apache Kyuubi via unprefixed Spark config aliases, potentially accessing unauthorized files.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 31 Jul 2026
- **Updated:** 31 Jul 2026
- **Also known as:** GHSA-pp6r-c7gq-g5pr

## What is CVE-2026-62391?

CVE-2026-62391 is a high-severity path traversal vulnerability in Apache Kyuubi, published on 31 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official 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.

Weakness: CWE-27 (Path Traversal: 'dir/../../filename'), CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-62391?

It affects 1 product.


Products: Apache Kyuubi.

## How do I fix CVE-2026-62391?

No fix has been published for CVE-2026-62391 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-62391 being exploited?

There is no known exploitation of CVE-2026-62391 in the wild and no public exploit code.

## Other vulnerabilities in Apache Kyuubi

- [CVE-2026-52680](https://insights.sbomify.com/CVE-2026-52680/): Apache Kyuubi: REST batch multipart upload path traversal allows controlled file write (critical 9.8)
- [CVE-2025-66518](https://insights.sbomify.com/CVE-2025-66518/): Apache Kyuubi: Unauthorized directory access due to missing path normalization (high 8.8)
- [CVE-2026-23904](https://insights.sbomify.com/CVE-2026-23904/): Apache Kyuubi: Unrestricted access via Kyuubi engine-ui proxy (high 7.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-62391 and fix it if it is affected.

What it is: CVE-2026-62391 is a high-severity path traversal vulnerability in Apache Kyuubi, published on 31 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-62391 in the wild and no public exploit code.

Affected product: Apache Kyuubi. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-62391/ (Markdown: https://insights.sbomify.com/CVE-2026-62391/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-62391
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-62391
- OSV: https://osv.dev/vulnerability/CVE-2026-62391

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-62391/
Summaries are generated and may contain mistakes; the official description above is the record.