CVE-2026-72765 in n8n
Summary
by MITRE • 08/11/2026
n8n before 2.31.5 and before 2.32.1 contain a sandbox escape vulnerability in expression evaluation. An authenticated user with permission to create or modify workflows can craft expressions using arrow-function bodies to bypass the expression sandbox, triggering system command execution on the host running n8n. The issue is fixed in versions 2.31.5 and 2.32.1.
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Analysis
by VulDB Data Team • 08/11/2026
The vulnerability under discussion represents a critical sandbox escape flaw in the n8n workflow automation platform affecting versions prior to 2.31.5 and 2.32.1. This security weakness resides within the expression evaluation system that processes user-defined expressions within workflow configurations, creating a pathway for authenticated attackers to circumvent intended execution boundaries. The vulnerability specifically leverages the use of arrow function bodies in expression syntax to break out of the restricted sandbox environment designed to prevent unauthorized system access.
The technical implementation of this flaw exploits the way n8n processes user-supplied expressions during workflow execution. When users create or modify workflows, they can define expressions that are evaluated within a controlled sandbox environment intended to limit access to system resources and prevent arbitrary code execution. However, the vulnerability allows attackers to craft malicious expressions using arrow function syntax that can bypass these protective mechanisms. The exploitation occurs through careful construction of expression payloads that leverage JavaScript's prototype chain traversal and object property access patterns to gain elevated privileges within the evaluation context.
From an operational impact perspective, this vulnerability presents a severe risk to organizations relying on n8n for workflow automation, as it enables authenticated users with workflow creation or modification permissions to execute arbitrary system commands on the host machine running the n8n service. The implications extend beyond simple privilege escalation, as successful exploitation could allow attackers to access sensitive data, modify system configurations, install malware, or establish persistent access points within the environment. This represents a direct violation of the principle of least privilege and undermines the fundamental security assumptions of the platform's architecture.
The vulnerability aligns with CWE-74 and CWE-94 categories from the Common Weakness Enumeration framework, specifically addressing code injection vulnerabilities and improper restriction of operations within a sandboxed environment. It also maps to several ATT&CK techniques including T1059.007 for command and scripting interpreter and T1566 for malicious file execution, as the exploitation enables arbitrary command execution on target systems. Organizations should implement immediate mitigations including updating to patched versions 2.31.5 or 2.32.1, reviewing user permissions to minimize workflow modification access, and monitoring for suspicious expression patterns within workflow configurations. Additional defensive measures might include network segmentation of n8n instances, implementing strict input validation for expression fields, and conducting regular security assessments of automation workflows to identify potential exploitation vectors.