Threat Intelligence Database

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.

CVE-2026-86242 is a high-severity vulnerability in maximhq Bifrost HTTP transport versions before 2.0.0-prerelease3. It allows unauthenticated remote code execution when management authentication is disabled (the default setting). The flaw arises because Bifrost accepts a custom plugin path as an HTTP URL, downloads it, and dynamically loads it as a Go plugin, executing initialization code with the Bifrost process user privileges. This dynamic loading only succeeds on dynamically linked builds; statically linked Docker images are not vulnerable to RCE but may be susceptible to server-side request forgery. The vulnerability requires high attack complexity due to environment-specific plugin compatibility requirements. The 1.6.x line through 1.6.11 is also affected. No official patch or remediation link is provided in the data.