Onyx 4.6.6 fails to properly restrict access to custom tool credentials stored in custom_headers, allowing any authenticated user to read admin-defined API keys. Attackers with basic authentication can call GET /tool/{tool_id} or GET /tool endpoints to retrieve plaintext authorization headers and third-party API credentials, then use them to directly access upstream APIs.

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation poc

Automatable no

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
onyx-dot-app onyx unaffected
Version Status Constraints
0 affected ≤ 4.6.6

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

No data.

Project Subscriptions

Vendors Products
Onyx Subscribe
Onyx Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/onyx-dot-app/onyx cve-icon cve-icon
https://github.com/onyx-dot-app/onyx/blob/v4.6.6/backend/onyx/server/features/tool/api.py cve-icon cve-icon
https://github.com/onyx-dot-app/onyx/blob/v4.6.6/backend/onyx/server/features/tool/models.py cve-icon cve-icon
https://github.com/onyx-dot-app/onyx/issues/13165 cve-icon cve-icon
https://www.vulncheck.com/advisories/onyx-4.6.6-custom-tool-secret-header-disclosure-via-tool-endpoints cve-icon cve-icon
History

Fri, 04 Sep 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Fri, 04 Sep 2026 14:45:00 +0000

Type Values Removed Values Added
Description Onyx 4.6.6 fails to properly restrict access to custom tool credentials stored in custom_headers, allowing any authenticated user to read admin-defined API keys. Attackers with basic authentication can call GET /tool/{tool_id} or GET /tool endpoints to retrieve plaintext authorization headers and third-party API credentials, then use them to directly access upstream APIs.
Title Onyx 4.6.6 Custom Tool Secret Header Disclosure via Tool Endpoints
First Time appeared Onyx
Onyx onyx
Weaknesses CWE-522
CPEs cpe:2.3:a:onyx:onyx:*:*:*:*:*:*:*:*
Vendors & Products Onyx
Onyx onyx
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'}

cvssV4_0

{'score': 7.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-09-04T14:55:15.464Z

Reserved: 2026-09-04T13:51:53.585Z

Link: CVE-2026-85700

cve-icon Vulnrichment

Updated: 2026-09-04T14:53:27.543Z

cve-icon NVD

Status : Received

Published: 2026-09-04T15:17:49.110

Modified: 2026-09-04T15:17:49.110

Link: CVE-2026-85700

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-04T15:45:04Z

Weaknesses