Auth bypass in Onyx-Dot-App Onyx

CVE-2026-63178

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.

Vulnerability class: IDOR (Insecure Direct Object Reference)

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-63178?
CVE-2026-63178 is a medium-severity vulnerability in Onyx-Dot-App Onyx, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-08-17.
How severe is CVE-2026-63178?
Medium severity. CVSS v3 base score is 6.5 out of 10.