Secuno
ENNL
Book demo

CVE-2026-54309

N8n authentication bypass

10.0 CRITICALEPSS 0.55%
  1. Published23 Jun 2026

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.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeChanged
ConfidentialityHigh
IntegrityHigh
AvailabilityLow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:L

Affected products

N8n≥ 2.26.0 < 2.26.2 · < 2.25.7

Remediation

Fixed in
N8n≥ 2.26.2

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-876899.8
The Metasploit Framework Web Service REST API (msf-ws) exposes the credential store…
CVE-2026-843138.8
Nginx UI is a web user interface for the Nginx web server. Prior to 2.4.1, POST…
CVE-2026-1095759.8
In HAProxy Data Plane API 2.2.0 through 3.4.3 (and corresponding Enterprise Edition…
CVE-2026-571189.8
PraisonAI is a multi-agent teams system. Prior to praisonaiagents 1.6.59,…
CVE-2026-1093718.2
ZITADEL 3.0.0 before 4.18.0 contains a missing authentication vulnerability in the…
CVE-2026-1085498.1
cc-connect through 1.5.0 contains a missing authentication vulnerability in the MAX…

Frequently asked

Is CVE-2026-54309 being actively exploited?

CVE-2026-54309 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.55%.

How severe is CVE-2026-54309?

CVE-2026-54309 has a CVSS 3.1 base score of 10.0, rated critical. EPSS estimates a 0.55% probability of exploitation.

Which products are affected by CVE-2026-54309?

Affected products include N8n.

How do I fix CVE-2026-54309?

Upgrade affected software to a fixed version, for example N8n 2.26.2 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-54309 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.