CyberSecBulletin
CVE-2026-72769NVD status: Analyzed

n8n: Improperly Controlled Modification of Object Prototype Attributes

Published Updated By the CyberSecBulletin desk

CVE-2026-72769 is a high-severity improperly controlled modification of object prototype attributes vulnerability in n8n, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 1.123.67, 2.32.1, 2.31.5 as the first without the flaw, so updating n8n to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.51% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update n8n to 1.123.67 or 2.32.1 or 2.31.5, whichever matches your release line, or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
n8nn8nbefore 1.123.67; 2.32.0 up to, but not including, 2.32.1; 2.0.0-rc.0 up to, but not including, 2.31.51.123.67, 2.32.1, 2.31.5

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.06.1MediumCNA (vulncheck.com)
CVSS 3.18.1HighNVD

Official description

n8n before 1.123.67, 2.31.5, and 2.32.1 contains a prototype pollution vulnerability in the VM expression engine. An authenticated user able to create or edit a workflow expression can abuse the engine's array-element access to obtain a reference to a host built-in and pollute its prototype in the main n8n process (a sandbox escape), leading to a denial of service. Both self-hosted and cloud instances running the VM expression engine are affected.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improperly Controlled Modification of Object Prototype Attributes

The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.

How developers prevent this class of flaw

  • By freezing the object prototype first (for example, Object.freeze(Object.prototype)), modification of the prototype becomes impossible.
  • By blocking modifications of attributes that resolve to object prototype, such as proto or prototype, this weakness can be mitigated.
  • When handling untrusted objects, validating using a schema can be used.

More Improperly Controlled Modification of Object Prototype Attributes vulnerabilities (CWE-1321)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in n8n

All n8n vulnerabilities

Recent Improperly Controlled Modification of Object Prototype Attributes vulnerabilities

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