CVE-2026-63178

Onyx Curator-scope IDOR: any curator can modify membership of arbitrary user groups via unscoped PATCH /manage/admin/user-group/{id} and /add-users leading to cross-group document disclosure

6.5 Medium

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: High
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: None

Exploit likelihood

0.52%Up 0.2 points since Aug 18, 2026

What each source reports

CVE List Score used 6.5

Onyx Curator-scope IDOR: any curator can modify membership of arbitrary user groups via unscoped PATCH /manage/admin/user-group/{id} and /add-users leading to cross-group document disclosure

Record: CVE-2026-63178
CVSS 3.1: 6.5 MediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Weakness: CWE-639
Updated: 2026-11-02

EUVDEUVD-2026-60497 6.5

Record: EUVD-2026-60497
CVSS 3.1: 6.5 MediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Updated: 2026-11-02

NVD 6.5

Record: CVE-2026-63178
CVSS 3.1: 6.5 MediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Weakness: CWE-639
Updated: 2026-11-02

OSV 6.5

Onyx Curator-scope IDOR: any curator can modify membership of arbitrary user groups via unscoped PATCH /manage/admin/user-group/{id} and /add-users leading to cross-group document disclosure

Record: CVE-2026-63178
CVSS 3.1: 6.5 MediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
Weakness: CWE-639
Updated: 2026-11-02

Affected products

onyx-dot-app onyx

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2026-63178 is a medium vulnerability (CVSS 6.5) in Onyx-dot-app Onyx, published August 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.52%, the 44th percentile. No source names a fixed version.