Vulnerability · Published Sep 8, 2026 · Assigned by GitHub_M

CVE-2026-86076n8n: Expression Sandbox Escape in Editor-UI Enables Stored Cross-User JavaScript Execution

High 8.7

In plain English

A high-severity code injection in n8n from n8n-io. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 57% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)8.7High

Exploit odds (30 days)0.8%top 43.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack tooling1Public PoC

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	n8n	1.123.76	GHSA-hw8v-xxg5-vvvx
npm	n8n	2.38.2	GHSA-hw8v-xxg5-vvvx
npm	n8n	2.37.7	GHSA-hw8v-xxg5-vvvx

Affected products (as reported)

Vendor	Product	Versions
n8n-io	n8n	>= 2.38.0, < 2.38.2>= 2.0.0, < 2.37.7< 1.123.76

Weakness: CWE-94 · 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

References

https://github.com/n8n-io/n8n/security/advisories/GHSA-hw8v-xxg5-vvvx x_refsource_CONFIRM
https://github.com/n8n-io/n8n/releases/tag/n8n@1.123.76 x_refsource_MISC
https://github.com/n8n-io/n8n/releases/tag/n8n@2.37.7 x_refsource_MISC
https://github.com/n8n-io/n8n/releases/tag/n8n@2.38.2 x_refsource_MISC