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.
CVE-2026-54309
This critical-severity CVE scores 10.0 under NVD CVSS v3. EPSS exploit probability: 0.4%, top 67% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 10.0
- EG Score
- 10.0(medium)
- EPSS
- 32.9%
- KEV
- Not listed
Published
June 16, 2026
Last Modified
June 25, 2026
Advisory Details (1)
Auto-updated Jul 17, 2026n8n MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions · Advisory · n8n-io/n8n · GitHub
https://github.com/n8n-io/n8n/security/advisories/GHSA-qrx8-25qr-5r7vVendor Advisories for CVE-2026-54309(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
npm(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| n8n | — | 2.25.7 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 44× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-22 14:08 UTCEPSS rescore
- 2026-07-21 15:25 UTCEPSS rescore
- 2026-07-20 17:08 UTCEPSS rescore
- 2026-07-19 14:31 UTCEPSS rescore
- 2026-07-19 14:31 UTCEPSS rescore
- 2026-07-19 02:29 UTCEPSS rescore
- 2026-07-18 10:04 UTCEPSS rescore
- 2026-07-16 17:03 UTCEPSS rescore
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 16:57 UTCEPSS rescore
- 2026-07-15 02:00 UTCEPSS rescore
- 2026-07-15 02:00 UTCEPSS rescore
- 2026-07-13 22:31 UTCEPSS rescore
- 2026-07-13 06:13 UTCEPSS rescore
- 2026-07-13 06:13 UTCEPSS rescore
- 2026-07-12 05:46 UTCEPSS rescore
- 2026-07-11 08:27 UTCEPSS rescore
- 2026-07-11 08:27 UTCEPSS rescore
- 2026-07-09 19:10 UTCEPSS rescore
- 2026-07-09 19:10 UTCEPSS rescore
- 2026-07-08 15:16 UTCEPSS rescore
- 2026-07-08 15:16 UTCEPSS rescore
- 2026-07-07 13:46 UTCEPSS rescore
- 2026-07-07 13:46 UTCEPSS rescore
- 2026-07-06 16:27 UTCEPSS rescore
Show 20 moreShow fewer
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-01 15:07 UTCEPSS rescore
- 2026-06-30 23:22 UTCEPSS rescore
- 2026-06-29 14:06 UTCEPSS rescore
- 2026-06-29 14:06 UTCEPSS rescore
- 2026-06-28 14:07 UTCEPSS rescore
- 2026-06-28 04:56 UTCEPSS rescore
- 2026-06-28 04:56 UTCEPSS rescore
- 2026-06-27 03:08 UTCEPSS rescore
- 2026-06-26 11:49 UTCEG score recompute▲ 1.20
- 2026-06-25 19:49 UTCNVD updateCVSS v3 → 10 · severity → CRITICAL
- 2026-06-25 13:49 UTCEPSS rescore
- 2026-06-24 14:05 UTCEPSS rescore
- 2026-06-23 19:16 UTCEG score recompute▼ 1.20
- 2026-06-23 15:45 UTCMITRE cvelistV5CVSS v3 → 8.8 · CVSS v4 → 8.8
- 2026-06-16 23:44 UTCEG score recompute
Related CVEs(same CWE)
Same CWE
10 shownCWE-306
- CVE-2011-10013EG 10.0CRITICAL
- CVE-2014-125124EG 10.0CRITICAL
- CVE-2017-2637EG 10.0EPSS 91%CRITICAL
- CVE-2010-5326EG 10.0 KEVEPSS 97%CRITICAL
- CVE-2018-25134EG 9.8CRITICAL
- CVE-2012-10030EG 9.8CRITICAL
- CVE-2018-21132EG 9.8CRITICAL
- CVE-2014-3449EG 9.8CRITICAL
- CVE-2006-0062EG 9.8CRITICAL
- CVE-2006-0061EG 9.8CRITICAL
Frequently asked(5)
What is CVE-2026-54309?
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Dependency Blast Radius
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