CVE-2026-86078

n8n: Prototype Pollution via Workflow Structure Summary Can Lead to Denial of Service

Published: Sep 8, 2026Updated: Sep 11, 2026 Sources: CVE List NVDCWE-1321

6.5MEDIUM

Description

n8n is an open source workflow automation platform. Prior to 2.37.7 and 2.38.2, the Instance AI workflow summary used node names and connection keys from stored workflows as ordinary object keys. A workflow submitted through the REST API could contain __proto__ or constructor, causing nested writes to reach Object.prototype in the main n8n process and disrupt later requests. The affected function is summarizeWorkflowStructure in packages/@n8n/instance-ai/src/tools/workflows/summarize-workflow.ts. This issue is fixed in versions 2.37.7 and 2.38.2.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-1321

Affected Products

n8n-io

commercial·DEaka n8n

n8nOn-premWeb App

Cloud & SaaS / container-orchestration

n8n

oss-project

n8nSaaSWeb App

Cloud & SaaS / saas-application

Exploitability

Workaround Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Execution

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References

https://github.com/n8n-io/n8n/security/advisories/GHSA-679f-58pq-4v2c

github.com

https://github.com/n8n-io/n8n/releases/tag/n8n@2.37.7

github.com

https://github.com/n8n-io/n8n/releases/tag/n8n@2.38.2

github.com

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