CVE-2026-34200: Nhost CLI MCP Server: Missing Inbound Authentication on Explicitly Bound Network Port
Vulnerability summary
CVE-2026-34200 is a high (CVSS 7.7) vulnerability in nhost cli. EPSS estimates a 0.38% chance of exploitation in the next 30 days, higher than 31.4% of scored vulnerabilities. 1 public exploit is recorded.
Public exploit (GitHub, Date unknown)
Source freshness unavailable
How is this decided?Timeline
- 31-03-2026PublishedVulnerability first disclosed.
- 31-03-2026Last modifiedVulnerability information updated.
Description
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 metrics
3 scores · 2 sources · 2 versions- NVDNIST7.7HighCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS trend
Probability
0.38%
Chance of exploitation in the next 30 days
Percentile
31%
Versus all other CVEs
30-day change
Decrease -0.22 pp
From 0.60% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundNhost
Maturity: poc
Weaknesses
CWE · root cause- CWE-306Missing Authentication for Critical FunctionalityThe product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
- CWE-942Permissive Cross-domain Security Policy with Untrusted DomainsThe product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.
Affected systems
Known conditions: network-reachable, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.
1 vendor · 2 products
References
3 links- github.com/nhost/nhost/security/advisories/GHSA-6c5x-3h35-vvw2X Refsource CONFIRMExploitVendor Advisory