CVE-2026-54309 — n8n: n8n MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions

Description (CNA)

n8n is an open source workflow automation platform. Prior to 2.25.7 and 2.26.2, when @n8n/mcp-browser is run in HTTP transport mode, the MCP endpoint accepts session initialization and tool invocation requests without any authentication. Any network-reachable client, or any website visited by the user, can establish an MCP session and invoke browser-control tools. Where the n8n AI Browser Bridge extension is installed and a browser connection is active, an unauthenticated caller can access browser-control capabilities including navigation, JavaScript evaluation, and cookie and storage access against the user's real browser profile. This issue only affects instances where @n8n/mcp-browser is run with the HTTP transport (--transport http). This vulnerability is fixed in 2.25.7 and 2.26.2.

Affected (CNA)

Vendor / product	Versions
n8n-io / n8n	affected >= 2.26.0, < 2.26.2; affected < 2.25.7

CWE

CWE-306

References

https://github.com/n8n-io/n8n/security/advisories/GHSA-qrx8-25qr-5r7v

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.