CVE-2026-90898
Critical · CVSS 9.8- CVSS
- 9.8
- nvd
- EPSS
- —
- KEV
- No
- Class
- oss containerizable
- CWE-284, CWE-306
Description
Bifrost registers MCP clients through its management API. A stdio client is a command plus args. Bifrost starts that program in the gateway the moment the client is added. No MCP handshake required. The default is governance.auth_config.is_enabled=false. Auth off means every caller is a local admin. One unauthenticated POST /api/mcp/client is enough to run a program as the Bifrost process user (appuser on the official image). transports/v2.1.0 refuses an unauthenticated stdio registration with 403. transports/v2.0.0 still allows it.
References
Status: profiled · ingested 2026-09-19T00:00:27.000Z