# CVE-2026-63178: Onyx authorization bypass in user group management

Source: https://junglewise.ai/threats/cve-2026-63178-onyx-authorization-bypass-in-user-group-management  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-17. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-63178 · Severity: medium · CVSS 6.5 · Published 2026-08-17

Onyx is an open-source AI platform that manages user access and document permissions. Prior to version 4.3.0, the Enterprise Edition failed to properly validate permissions when curators modified user groups, allowing a curator to add users to arbitrary groups and gain unauthorized access to documents they should not see. This could result in sensitive data exposure through unauthorized document access.

Vendors: [Onyx](https://junglewise.ai/threats/vendors/onyx).

## Quick answers

**Is CVE-2026-63178 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-63178 being exploited in the wild.

**How severe is CVE-2026-63178?** Medium severity, with a CVSS score of 6.5, published 17 August 2026.

**Which products and versions are affected?** Onyx Enterprise Edition before 4.3.0.

**Is there a fix for CVE-2026-63178?** A patch was published on 2026-06-30: Fix released in version 4.3.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-63178 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-63178?** Check whether you run Onyx Enterprise Edition at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is an authorization bypass in the user group management API endpoints. The 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 failed to call the _validate_curator_can_modify_group authorization check when invoking update_user_group and add_users_to_user_group functions in ee/onyx/db/user_group.py. An authenticated curator can exploit this to add arbitrary user accounts to groups they do not manage, then use the get_acl_for_user function and OpenSearch access_control_list filter to access documents assigned to those groups. The vulnerability was fixed in version 4.3.0 by implementing proper authorization validation on curator group modifications.

## Affected products

- Onyx Onyx Enterprise Edition before 4.3.0

## Timeline

- 2026-08-17: disclosed
- 2026-06-30: patched: Fix released in version 4.3.0

## References

- [https://github.com/onyx-dot-app/onyx/commit/46e19cc2750fed659488cb12a1f171016ba5a099](https://github.com/onyx-dot-app/onyx/commit/46e19cc2750fed659488cb12a1f171016ba5a099)
- [https://github.com/onyx-dot-app/onyx/commit/b9e1c6894be3c237283f4b5fd4eb0af935b40664](https://github.com/onyx-dot-app/onyx/commit/b9e1c6894be3c237283f4b5fd4eb0af935b40664)