CVE-2026-33696
Published: 25 March 2026
Summary
CVE-2026-33696 is a high-severity Prototype Pollution (CWE-1321) vulnerability in N8N N8N. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 39.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 AC-6 (Least Privilege) and SI-10 (Information Input Validation).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Requires timely patching to fixed n8n versions 2.14.1, 2.13.3, or 1.123.27, fully remediating the prototype pollution vulnerability.
Enforces validation of information inputs to XML and GSuiteAdmin nodes, preventing crafted parameters from polluting Object.prototype and enabling RCE.
Implements least privilege by restricting workflow creation and modification permissions to fully trusted users, directly aligning with recommended temporary mitigation.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Prototype pollution vulnerability allows authenticated low-privilege users (PR:L) to achieve remote code execution (RCE) on the n8n instance, directly enabling Exploitation for Privilege Escalation.
NVD Description
n8n is an open source workflow automation platform. Prior to versions 2.14.1, 2.13.3, and 1.123.27, an authenticated user with permission to create or modify workflows could exploit a prototype pollution vulnerability in the XML and the GSuiteAdmin nodes. By supplying…
more
a crafted parameters as part of node configuration, an attacker could write attacker-controlled values onto `Object.prototype`. An attacker could use this prototype pollution to achieve remote code execution on the n8n instance. The issue has been fixed in n8n versions 2.14.1, 2.13.3, and 1.123.27. Users should upgrade to one of these versions or later to remediate the vulnerability. If upgrading is not immediately possible, administrators should consider the following temporary mitigations: Limit workflow creation and editing permissions to fully trusted users only, and/or disable the XML node by adding `n8n-nodes-base.xml` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
Deeper analysisAI
CVE-2026-33696 is a prototype pollution vulnerability (CWE-1321) affecting the XML and GSuiteAdmin nodes in n8n, an open-source workflow automation platform. The flaw impacts versions prior to 2.14.1, 2.13.3, and 1.123.27, where crafted parameters in node configurations allow writing attacker-controlled values to Object.prototype. It carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
An authenticated user with permissions to create or modify workflows can exploit the vulnerability remotely with low complexity and no user interaction required. By injecting specially crafted parameters into the affected nodes, the attacker pollutes the Object prototype, enabling remote code execution on the n8n instance.
The issue is patched in n8n versions 2.14.1, 2.13.3, and 1.123.27; users should upgrade to these or later releases for full remediation. Temporary mitigations include restricting workflow creation and editing to fully trusted users only and/or disabling the XML node by adding "n8n-nodes-base.xml" to the NODES_EXCLUDE environment variable. These workarounds are short-term and incomplete. Additional details are in the advisory at https://github.com/n8n-io/n8n/security/advisories/GHSA-mxrg-77hm-89hv.
Details
- CWE(s)