Nhost is an open source Firebase alternative with GraphQL. In versions of Nhost CLI prior to 1.46.0, the hidden `nhost configserver` used by `nhost dev` exposes the Mimir GraphQL API with dummy authorization directives and permissive CORS. When a developer is running the local development environment, any process that can reach the developer's localhost service, including a web page loaded from an arbitrary origin, can query the configserver for local Nhost configuration and secrets and can mutate the local `.secrets` file. This impacts developers using `nhost dev`: project admin secrets, JWT signing keys, webhook secrets, Grafana credentials, and custom environment variables can be read, and attacker-controlled secrets can be written to the local development project. Version 1.46.0 of Nhost CLI contains a fix.
CVSS Score
5.4
EPSS Score
0.003
Published
2026-07-21
Nhost is an open source Firebase alternative with GraphQL. Prior to version 1.41.0, The Nhost CLI MCP server, when explicitly configured to listen on a network port, applies no inbound authentication and does not enforce strict CORS. This allows a malicious website visited on the same machine to issue cross-origin requests to the MCP server and invoke privileged tools using the developer's locally configured credentials. This vulnerability requires two explicit, non-default configuration steps to be exploitable. The default nhost mcp start configuration is not affected. This issue has been patched in version 1.41.0.
CVSS Score
7.7
EPSS Score
0.004
Published
2026-03-31