# CVE-2026-63178: Missing authorization in onyx

> Curators can modify arbitrary user group memberships to gain unauthorized access to documents due to missing authorization checks.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 17 Aug 2026
- **Updated:** 18 Aug 2026
- **Also known as:** GHSA-7f48-vgpj-h95m

## What is CVE-2026-63178?

CVE-2026-63178 is a medium-severity missing authorization vulnerability in onyx-dot-app onyx, published on 17 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Onyx is an open-source AI platform. Prior to 4.3.0, Onyx Enterprise Edition's PATCH /manage/admin/user-group/{user_group_id} and POST /manage/admin/user-group/{user_group_id}/add-users endpoints in ee/onyx/server/user_group/api.py call update_user_group and add_users_to_user_group in ee/onyx/db/user_group.py without enforcing _validate_curator_can_modify_group, allowing a curator to add accounts to arbitrary groups and obtain document access through get_acl_for_user and the OpenSearch access_control_list filter. This issue is fixed in version 4.3.0.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-63178?


## How do I fix CVE-2026-63178?

No fix has been published for CVE-2026-63178 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-63178 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-63178 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-63178 and fix it if it is affected.

What it is: CVE-2026-63178 is a medium-severity missing authorization vulnerability in onyx-dot-app onyx, published on 17 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-63178 exists.

Affected product: onyx-dot-app onyx. 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-2026-63178/ (Markdown: https://insights.sbomify.com/CVE-2026-63178/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-63178
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63178
- OSV: https://osv.dev/vulnerability/CVE-2026-63178

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-63178/
Summaries are generated and may contain mistakes; the official description above is the record.