Critical Remote Code Execution Vulnerability in n8n Workflow Automation Platform
A critical remote code execution vulnerability, tracked as CVE-2026-21877, has been identified in the n8n workflow automation platform. The flaw, rated CVSS 10.0, allows authenticated users to execute arbitrary code on affected n8n instances, posing a significant risk to environments where n8n is used to automate workflows with access to sensitive data, internal systems, and credentials. The vulnerability impacts n8n versions from 0.123.0 up to but not including 1.121.3, affecting both self-hosted and managed deployments. Exploitation requires authenticated access, and the vulnerability is linked to unsafe handling that can result in the execution of untrusted code.
The issue has been addressed in n8n version 1.121.3 and later, and users are strongly advised to upgrade immediately to mitigate the risk. Additional recommendations include restricting workflow modification access to trusted administrators, blocking high-risk nodes at runtime, and reviewing audit logs for suspicious activity prior to patching. No public exploit details or proof-of-concept have been released as of the latest advisories. Organizations using n8n should prioritize patching and implement hardening measures to prevent potential compromise of their automation infrastructure.

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How this story unfolded
2 events from the most recent confirmed update back to the earliest known activity.
Public disclosure details CVE-2026-21877 as CVSS 10.0 flaw
Security reporting disclosed CVE-2026-21877 as a maximum-severity vulnerability in n8n that could let authenticated attackers execute arbitrary code and potentially take full control of affected instances. At the time of disclosure, no public exploit or proof-of-concept was reported.
n8n patches critical authenticated RCE in version 1.121.3
n8n fixed CVE-2026-21877, a critical authenticated remote code execution flaw affecting versions 0.123.0 through 1.121.2, in version 1.121.3. The vulnerability stems from unsafe handling that can lead to execution of untrusted code on both self-hosted and managed deployments.
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