n8n is an open source workflow automation platform. Prior to 1.123.76, 2.37.7, and 2.38.2, the expression compiler sanitizer resolved through dynamically scoped this and did not reject reserved class member names. A class field named __sanitize could rebind the sanitizer and reach the Function constructor, enabling backend code execution and editor-preview JavaScript execution. The affected AST hook is PrototypeSanitizer in packages/workflow/src/expression-sandboxing.ts. This issue is fixed in versions 1.123.76, 2.37.7 and 2.38.2.
History

Wed, 09 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 08 Sep 2026 21:45:00 +0000

Type Values Removed Values Added
Description n8n is an open source workflow automation platform. Prior to 1.123.76, 2.37.7, and 2.38.2, the expression compiler sanitizer resolved through dynamically scoped this and did not reject reserved class member names. A class field named __sanitize could rebind the sanitizer and reach the Function constructor, enabling backend code execution and editor-preview JavaScript execution. The affected AST hook is PrototypeSanitizer in packages/workflow/src/expression-sandboxing.ts. This issue is fixed in versions 1.123.76, 2.37.7 and 2.38.2.
Title n8n: Expression Sandbox Escape in Editor-UI Enables Stored Cross-User JavaScript Execution
Weaknesses CWE-94
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-09-08T21:28:52.762Z

Updated: 2026-09-09T15:33:55.770Z

Reserved: 2026-09-04T19:34:03.100Z

Link: CVE-2026-86076

cve-icon Vulnrichment

Updated: 2026-09-09T15:33:50.483Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-09-08T22:19:16.387

Modified: 2026-09-09T20:16:54.383

Link: CVE-2026-86076

cve-icon Redhat

No data.