External risk intelligence

n8n Prototype Pollution Leading to RCE

CVE advisorySeverity: CRITICAL (CVSS 9.4)

CVE-2026-44789

n8n is a workflow automation platform frequently deployed as a web-based service accessible over the network. As an automation engine that integrates with various external web services, these instances are commonly exposed to the internet or reachable within organizational network perimeters to facilitate cross-service communication.

N8n

before 1.123.432.0.0 to before 2.20.72.21.0 to before 2.22.1

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory details a critical vulnerability in the n8n workflow automation platform that could allow an authenticated user to execute arbitrary code on the affected instance. The issue stems from a flaw in how certain parameters are handled, which, when combined with other techniques, can lead to a compromise of the entire system. While this vulnerability is fixed in later versions, its potential impact on automated processes and connected systems warrants attention to confirm relevance and exposure.

Workflow automation tool has a critical security flaw.
Attack could allow code execution on company systems.
Confirm relevance and exposure to automated workflows.

Attack Path

How an attacker could exploit the issue

An attacker with permissions to create or modify workflows could exploit a flaw in the HTTP Request node. By manipulating an unvalidated pagination parameter, they can trigger a global prototype pollution vulnerability. This, when combined with other techniques, could lead to remote code execution on the n8n instance.

Authenticated user with workflow creation/modification permission.
Unvalidated pagination parameter in HTTP Request node.
Potential for remote code execution on the instance.

Live Threat

Current exploitation, exposure, and threat context

When supported by the advisory, an authenticated user with workflow modification permissions could exploit this vulnerability by manipulating an unvalidated pagination parameter within the HTTP Request node. This, combined with other techniques, could lead to the execution of arbitrary code on the n8n instance.

Workflow data and system integrity could be at risk.
Malicious input via HTTP Request node parameters.
Potential for arbitrary code execution on the instance.

Operational Fix

Recommended remediation, mitigation, and detection steps

The n8n workflow automation platform, when deployed and exposed, may require action from platform or application owners responsible for its instances. The first practical step involves identifying all n8n deployments, assessing their network reachability and criticality, and then coordinating remediation with the responsible teams.

Platform and application owners should lead.
Verify instance exposure and business criticality.
Plan remediation based on confirmed risk.

Supplementary metadata

CVSS vector

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Frequently asked questions

What is n8n and what is it used for?

n8n is an open-source workflow automation platform. Users leverage it to connect various applications, APIs, and databases, creating complex automated tasks that trigger actions between services. It acts as a central engine for data movement and process synchronization within an environment.

What is the prototype pollution weakness in CVE-2026-44789?

This vulnerability is classified as CWE-1321, or Improperly Controlled Modification of Object Prototype. It occurs when an application allows users to inject properties into the base object prototype. By manipulating this, an attacker can change the default behavior of the application, potentially leading to unauthorized execution of code.

How is this vulnerability triggered in n8n?

An attacker must have existing permissions to create or modify workflows to trigger the flaw. The attack uses an unvalidated pagination parameter within the HTTP Request node to inject malicious input. Standard usage of the node for legitimate pagination requests without this specific manipulation does not trigger the vulnerability.

Is my n8n instance at risk based on Halo Surface Signal?

Halo Surface Signal notes that n8n instances are frequently deployed as web-based services reachable over a network. If your instance is internet-facing or accessible to unauthorized internal users, the likelihood of a successful attack increases. You should evaluate your network reachability to determine if the instance is exposed to potentially untrusted users.

How do I secure my environment against this issue?

The primary response is to update your n8n software. This vulnerability is resolved in versions 1.123.43, 2.22.1, and 2.20.7. You should prioritize identifying all n8n instances in your network, verify their current version, and plan an upgrade to one of these patched releases as soon as possible.

References

github.com/n8n-io/n8n/security/advisories/GHSA-c8xv-5998-g76h

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.