CVE-2026-86076

highpriority · attend · 45EPSS 0.008 · 56 %ileexploit · PoCDEUS
grimoire priorityP1 · Urgent
Exploitable?
Public exploit
1 exploit · PoC
Likely / severe?
0.79% (56th) EPSS
CVSS 8.8 · high
Is it mine?
12 products
Check your exposure
Who says so?
3 sources
cert_bund · nvd · osv

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

8.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9
v4.08.7highCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · security-advisories@github.com
v4.07.4highCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-94USCWE-94US
04

exploits (1)

Public proof-of-concept and weaponised exploit code.

05

affected products (12)

Products and version ranges known to be affected.

06

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-3165n8n: Mehrere SchwachstellenDeutsch2026-09-02csaf · cert_bundDE

    Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in n8n ausnutzen, um Sicherheitsmechanismen zu umgehen, beliebigen Code auszuführen oder einen Denial of Service zu verursachen.

  • GHSA-hw8v-xxg5-vvvxn8n: Expression Sandbox Escape via Class-Field Sanitizer Rebinding Can Lead to Code Execution2026-09-10ghsa · osvUS

    ## Impact The expression compiler's sanitizer resolved through a dynamically-scoped `this`, so a class field named `__sanitize` rebound it and reached the `Function` constructor. On the backend, any expression author could run code in the n8n process; in the editor preview, a member's expression could run as JavaScript in the session of whoever opened the workflow. The patch rejects reserved class-member names. ## Patches The issue has been fixed in n8n versions 1.123.76, 2.37.7, and 2.38.2. Users should upgrade to one of these versions or later to remediate the vulnerability. ## Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Restrict n8n instance access to fully trusted users only. - Avoid granting workflow-create or workflow-edit permissions to untrusted users. - Audit existing workflows for unexpected or unfamiliar expressions in node parameters. - Set `N8N_EXPRESSION_ENGINE=vm`. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

07

sources

Which sources assert this record, and when.

cert_bundnvdosvNVDCVE.orgMITRE
published 2026-09-08modified 2026-09-11
08

references (4) nvd

External citations — patches, advisories, analysis.

scry

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