CVE-2026-54306: n8n Prototype Pollution Enables Confused-deputy Execution Vulnerability
MODERATECVE-2026-54306 is a MODERATE (CVSS 5.4) prototype pollution enables confused-deputy execution vulnerability (CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')) affecting n8n libraries in the npm ecosystem. The issue involves prototype pollution enables confused-deputy execution via public webhooks. Remediation is available by upgrading affected packages to version 2.26.2, 2.25.7.
CVE-2026-54306 at a Glance
Security Impact
CVSS: 5.4
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N).
How to Fix CVE-2026-54306
To remediate this vulnerability, upgrade all affected n8n dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
npm install n8n@2.26.2
npm install n8n@2.25.7
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls n8n
How to Check if You Are Affected
To determine whether your Node.js application is affected by CVE-2026-54306, inspect your project dependencies using npm:
npm ls n8n
Analyze the terminal output to locate any version of n8n in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.26.2), your application is affected.
Note: The npm ls n8n command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution'), where the product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. In n8n, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-54306 Affected n8n Versions
2 component(s)References
Frequently Asked Questions
What is CVE-2026-54306?
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What version fixes CVE-2026-54306?
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Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-2vff-hj5x-8gq7",
"modified" : "2026-07-20T13:45:14Z",
"published" : "2026-06-16T19:00:41Z",
"aliases" : [ "CVE-2026-54306" ],
"summary" : "n8n: Prototype Pollution enables confused-deputy execution via public webhooks",
"details" : "## Impact\nA prototype pollution vulnerability allowed a crafted public webhook payload to inject attacker-controlled fields into workflow data during internal object copying. These fields could be surfaced and consumed as normal values by downstream built-in nodes.\n\nWhere a workflow combines a public webhook with action nodes that consume the resulting fields, an attacker could cause the workflow to act as a confused deputy — targeting unintended records or issuing outbound requests using the workflow owner's configured credentials.\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 exposing public (unauthenticated) webhook workflows that pass incoming data through transform nodes into action nodes with sensitive credentials or database operations.\n- Limit workflow creation and editing permissions to fully trusted users only.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N"
}, {
"type" : "CVSS_V4",
"score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "n8n"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "2.26.0"
}, {
"fixed" : "2.26.2"
} ]
} ]
}, {
"package" : {
"ecosystem" : "npm",
"name" : "n8n"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "2.25.7"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/n8n-io/n8n/security/advisories/GHSA-2vff-hj5x-8gq7"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-54306"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/n8n-io/n8n"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-1321" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2026-06-16T19:00:41Z",
"nvd_published_at" : "2026-06-23T17:17:06Z"
}
}