CVE-2026-85700 Onyx 4.6.6 Custom Tool Secret Header Disclosure via Tool Endpoints
Authenticated users can retrieve plaintext admin API keys from custom tool endpoints, enabling unauthorized access to third-party services.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-85700?
CVE-2026-85700 is a high-severity vulnerability in onyx-dot-app onyx, published on 4 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-522
Which versions are affected by CVE-2026-85700?
How do I fix CVE-2026-85700?
No fix has been published for CVE-2026-85700 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-85700 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-85700 exists.
Sources
Also known as GHSA-jwfj-6q57-4cp3.