CVE-2026-34200CWE-306CWE-942

Nhost CLI MCP Server: Missing Inbound Authentication on Explicitly Bound Network Port

High · published March 31, 2026

CVSS v4.0
7.7
EPSS
1%
Percentile
47.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
7.7 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.00597 · 47.9th percentile
Weaknesses
CWE-306 · Missing Authentication for Critical Function; CWE-942 · Permissive Cross-domain Security Policy with Untrusted Domains
Published
2026-03-31T13:57Z
EPSS history
Timeline
  • 31 MAR 13:57Z
    Nhost CLI MCP Server: Missing Inbound Authentication on Explicitly Bound Network Port
    cvelistv5