CVE-2026-54309 (GCVE-0-2026-54309)

Vulnerability from cvelistv5 – Published: 2026-06-23 15:36 – Updated: 2026-06-23 15:45
VLAI
Title
n8n: n8n MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions
Summary
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.
Severity
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-306 - Missing Authentication for Critical Function
Assigner
References
Impacted products
Vendor Product Version
n8n-io n8n Affected: >= 2.26.0, < 2.26.2
Affected: < 2.25.7
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