{"id":"CVE-2026-54309","aliases":["EUVD-2026-38468","GHSA-qrx8-25qr-5r7v","ROOT-APP-NPM-CVE-2026-54309"],"status":"published","title":"n8n: n8n MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions","description":"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":{"version":"4.0","score":8.8,"vector":"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","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00546,"percentile":0.46216,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-306"],"published":"2026-06-16T23:32:31Z","modified":"2026-10-28T02:30:55Z","fixes":[{"ecosystem":"npm","package":"n8n","fixed_in":["2.26.2","2.25.7"],"sources":["ghsa","osv"]},{"ecosystem":"Root:npm","package":"n8n","fixed_in":["2.19.3-aikido.7","2.19.3-aikido.2","2.19.3-aikido.3","2.19.3-aikido.4","2.19.3-aikido.5","2.19.3-aikido.6","2.19.3-aikido.8","2.19.3-aikido.9","2.19.3-aikido.10","2.19.3-aikido.11","2.19.3-aikido.12","2.19.3-aikido.13","2.19.3-aikido.14","2.19.3-aikido.15"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"@rootio/n8n","fixed_in":["2.19.3-root.io.7","2.19.3-root.io.2","2.19.3-root.io.3","2.19.3-root.io.4","2.19.3-root.io.5","2.19.3-root.io.6","2.19.3-root.io.8","2.19.3-root.io.9","2.19.3-root.io.10","2.19.3-root.io.11","2.19.3-root.io.12","2.19.3-root.io.13","2.19.3-root.io.14","2.19.3-root.io.15"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"n8n","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.26.0"},{"fixed":"2.26.2"}]}]},{"source":"ghsa","ecosystem":"npm","package":"n8n","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.25.7"}]}]},{"source":"osv","ecosystem":"npm","package":"n8n","ranges":[{"type":"SEMVER","events":[{"introduced":"2.26.0"},{"fixed":"2.26.2"}]}]},{"source":"osv","ecosystem":"npm","package":"n8n","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.25.7"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"n8n","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.19.3-aikido.7"},{"fixed":"2.19.3-aikido.2"},{"fixed":"2.19.3-aikido.3"},{"fixed":"2.19.3-aikido.4"},{"fixed":"2.19.3-aikido.5"},{"fixed":"2.19.3-aikido.6"},{"fixed":"2.19.3-aikido.8"},{"fixed":"2.19.3-aikido.9"},{"fixed":"2.19.3-aikido.10"},{"fixed":"2.19.3-aikido.11"},{"fixed":"2.19.3-aikido.12"},{"fixed":"2.19.3-aikido.13"},{"fixed":"2.19.3-aikido.14"},{"fixed":"2.19.3-aikido.15"}]}]},{"source":"osv","ecosystem":"Root:npm","package":"@rootio/n8n","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.19.3-root.io.7"},{"fixed":"2.19.3-root.io.2"},{"fixed":"2.19.3-root.io.3"},{"fixed":"2.19.3-root.io.4"},{"fixed":"2.19.3-root.io.5"},{"fixed":"2.19.3-root.io.6"},{"fixed":"2.19.3-root.io.8"},{"fixed":"2.19.3-root.io.9"},{"fixed":"2.19.3-root.io.10"},{"fixed":"2.19.3-root.io.11"},{"fixed":"2.19.3-root.io.12"},{"fixed":"2.19.3-root.io.13"},{"fixed":"2.19.3-root.io.14"},{"fixed":"2.19.3-root.io.15"}]}]}],"products":[{"vendor":"n8n","product":"n8n"},{"vendor":"n8n-io","product":"n8n"}],"references":[{"url":"https://github.com/n8n-io/n8n/security/advisories/GHSA-qrx8-25qr-5r7v","tags":["x_refsource_CONFIRM","Mitigation","Vendor Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54309","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-qrx8-25qr-5r7v"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54309.json","tags":["advisory"]},{"url":"https://github.com/n8n-io/n8n","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-54309","title":"n8n: n8n MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions","description":"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.","status":"published","published":"2026-06-23T15:36:13.27Z","modified":"2026-06-23T15:45:15.836Z","cvss":[{"version":"4.0","score":8.8,"vector":"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","level":"high","assessor":"cna"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T13:38:09.774038Z"}],"euvd":[{"id":"EUVD-2026-38468","description":"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.","status":"published","published":"2026-06-23T15:36:13Z","modified":"2026-06-23T15:45:15Z","cvss":[{"version":"4.0","score":8.8,"vector":"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","level":"high"}],"updated_at":"2026-11-02T18:20:33.324654Z"}],"ghsa":[{"id":"GHSA-qrx8-25qr-5r7v","title":"n8n: MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions","description":"## Impact\nWhen `@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.\n\nWhere 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.\n\nThis issue only affects instances where `@n8n/mcp-browser` is run with the HTTP transport (`--transport http`). The default transport is stdio, which is not affected.\n\n## Patches\nThe issue has been fixed in n8n versions 2.25.7, and 2.26.2. Users should upgrade to one of these versions or later to remediate the vulnerability.\n\n## Workarounds\nIf upgrading is not immediately possible, administrators should consider the following temporary mitigations:\n- Avoid running `@n8n/mcp-browser` with the HTTP transport; use the default stdio transport instead.\n- If HTTP transport is required, restrict network access to the listening port to trusted clients only using host-based firewall rules.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.","status":"published","published":"2026-06-16T23:32:31Z","modified":"2026-07-20T13:39:51Z","cvss":[{"version":"4.0","score":8.8,"vector":"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","level":"high"},{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L","level":"critical"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T14:40:46.257074Z"}],"nvd":[{"id":"CVE-2026-54309","description":"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.","status":"published","published":"2026-06-23T16:17:01.86Z","modified":"2026-10-26T11:10:00.157Z","cvss":[{"version":"4.0","score":8.8,"vector":"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/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","level":"high","assessor":"secondary"},{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L","level":"critical","assessor":"primary"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T14:12:25.288279Z"}],"osv":[{"id":"CVE-2026-54309","title":"n8n: n8n MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions","description":"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.","status":"published","published":"2026-06-23T15:36:13.27Z","modified":"2026-10-28T02:30:55.188909895Z","cvss":[{"version":"4.0","score":8.8,"vector":"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","level":"high"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T15:45:10.818486Z"},{"id":"GHSA-qrx8-25qr-5r7v","title":"n8n: MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions","description":"## Impact\nWhen `@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.\n\nWhere 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.\n\nThis issue only affects instances where `@n8n/mcp-browser` is run with the HTTP transport (`--transport http`). The default transport is stdio, which is not affected.\n\n## Patches\nThe issue has been fixed in n8n versions 2.25.7, and 2.26.2. Users should upgrade to one of these versions or later to remediate the vulnerability.\n\n## Workarounds\nIf upgrading is not immediately possible, administrators should consider the following temporary mitigations:\n- Avoid running `@n8n/mcp-browser` with the HTTP transport; use the default stdio transport instead.\n- If HTTP transport is required, restrict network access to the listening port to trusted clients only using host-based firewall rules.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.","status":"published","published":"2026-06-16T23:32:31Z","modified":"2026-07-20T13:45:32.235949356Z","cvss":[{"version":"3.1","score":10,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L","level":"critical"},{"version":"4.0","score":8.8,"vector":"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","level":"high"}],"cwes":["CWE-306"],"updated_at":"2026-11-02T15:46:55.122811Z"},{"id":"ROOT-APP-NPM-CVE-2026-54309","title":"CVE-2026-54309 in n8n - Patched by Root","description":"Root has patched CVE-2026-54309 in the n8n package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-10-06T03:42:47Z","modified":"2026-10-06T04:15:03.043757818Z","updated_at":"2026-11-02T15:53:27.649662Z"}]}}