CVE-2026-86076

high

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.

References

https://github.com/n8n-io/n8n/security/advisories/GHSA-hw8v-xxg5-vvvx

https://github.com/n8n-io/n8n/releases/tag/[email protected]

https://github.com/n8n-io/n8n/releases/tag/[email protected]

https://github.com/n8n-io/n8n/releases/tag/[email protected]

Details

Source: Mitre, NVD

Published: 2026-09-08

Updated: 2026-09-09

Risk Information

CVSS v2

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Severity: High

CVSS v3

Base Score: 10

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Severity: Critical

CVSS v4

Base 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

Severity: High

EPSS

EPSS: 0.00334