---
cve: "CVE-2026-54309"
severity: "HIGH"
cvss: 8.8
epss: "40%"
vendor: "n8n-io"
kev: false
exploited: false
published: "2026-06-23 16:17:01"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-05T17:53:24+02:00"
---

# CVE-2026-54309

> 8.8 HIGH · 🧪 PoC

## Beschreibung

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.

## CVSS-Vektor

```
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
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- b06d9b5dfb9d8f709569e76a646a7ccc687db23c (Commit)
- b1f5f25dead5404d292c1dac53000e5ab128c343 (Commit)

## Referenzen

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

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-54309) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_