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TI-2026-74532 Aliases CVE-2026-110842

Prototype pollution in n8n MCP tool enables owner account takeover

Priority LOW 35CWE-1321Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

n8n before 2.41.4 and from 2.42.0 before 2.42.1 contains a prototype pollution flaw (CWE-1321) in its MCP workflow-validation tool. The tool's interpreter runs caller-supplied code in the main process and allows writes onto shared prototypes. An authenticated member with only the workflow:read grant can alter server-side permission checks, enabling takeover of owner accounts that lack MFA.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability in the MCP workflow-validation tool, whose interpreter evaluates caller-supplied code in the main process, reads inherited properties, and permits assignment onto shared prototypes. An authenticated member holding only a workflow:read grant can replace a built-in method with one returning a truthy value so server-side permission checks accept unheld scopes, enabling takeover of owner accounts not protected by MFA.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00312 24th percentileScored 2026-11-07
Fix Fixed n8n (n8n-io): 2.41.4, 2.42.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
n8nn8nbefore 2.41.4; 2.42.0 to before 2.42.12.41.4, 2.42.1Patch availableCNA
  • n8n Vendorn8n Affected before 2.41.4; 2.42.0 to before 2.42.1 Fixed in 2.41.4, 2.42.1 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*——n8n
  • cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:* Versions — — ·n8n

Remediation

Upgrade n8n to version 2.41.4 or 2.42.1.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA n8n (n8n-io) Fixed in 2.41.4, 2.42.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    n8n-io n8n 2.41.4, 2.42.1

    6 records Highest priority Priority LOW 6 LOW

    Other records, highest priority first

    • TI-2026-74536 Signature bypass in n8n Send-and-Wait waiting-webhook endpointPriority LOW 39
    • TI-2026-74530 SQL injection in n8n Microsoft SQL node via Query fieldPriority LOW 37
    • TI-2026-74533 Unbounded OAuth client creation in n8n lets attackers fill diskPriority LOW 35
    Show all 6 records →

Timeline

  1. 2026-10-15 Threatist record created from CVE-2026-110842
  2. 2026-10-15 CISA SSVC decision points changed
  3. 2026-10-15 Priority changed: MEDIUM → LOW

References

Advisory 1

  • TI-2025-42131 n8n Vulnerable to Remote Code Execution via Expression Injection KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-17560 n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling CVSS 3.1CRITICAL 10.0
  • TI-2026-01167 Authenticated users can bypass the Expression sandbox mechanism to achieve full remote… CVSS 3.1CRITICAL 9.9
  • TI-2026-00644 Sandbox escape in n8n Python task runner allows for arbitrary code execution on the underlying host. CVSS 3.1CRITICAL 9.9
  • TI-2026-82991 Code execution in n8n via deprecated Function nodes CVSS 4.0HIGH 8.7
  • TI-2025-35293 An arbitrary file upload vulnerability in the Chat Trigger component of N8N v1.95.3… CVSS 3.1HIGH 8.8
See all 233 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences