Onyx 4.6.6 Custom Tool Secret Header Disclosure via Tool Endpoints
Priority MEDIUM 64CWE-522Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-522.
Summary
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.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00511 43rd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| onyx-dot-app | onyx | up to 4.6.6 | — | No fix listed | CNA |
- onyx Vendoronyx-dot-app Affected up to 4.6.6 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-85700
- 2026-10-03 Alias added: GHSA-jwfj-6q57-4cp3
References
More onyx-dot-app vulnerabilities
- TI-2026-45084 Authorization bypass in onyx-dot-app onyx CVSS 3.1MEDIUM 6.5
- TI-2026-50048 Onyx: Cross-user OAuth-token leak via /api/mcp/servers* for per-user MCP servers CVSS 3.1CRITICAL 9.6
- TI-2026-80125 Cross-site scripting in onyx-dot-app Onyx PreviewTab.tsx CVSS 4.0MEDIUM 5.1
Sources
- CVE-2026-85700 · CVE Program
- CVE-2026-85700 · NVD
- FIRST EPSS
- GHSA-jwfj-6q57-4cp3 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences