Critical RCE Vulnerability in n8n Workflow Automation Platform (CVE-2026-21877)
Patch & Detection Intelligence · 2 sources · Updated 4mo ago · First seen Jan 7, 2026
A critical remote code execution (RCE) vulnerability, identified as CVE-2026-21877 and rated CVSS 10.0, was disclosed in the open-source workflow automation platform n8n. The flaw allows authenticated users to execute arbitrary code on affected instances, potentially leading to full system compromise. Both self-hosted and n8n Cloud deployments are impacted, specifically versions from 0.123.0 up to but not including 1.121.3. The vulnerability was discovered by security researcher Théo Lelasseux and has been addressed in version 1.121.3, released in November 2025. Administrators are strongly advised to upgrade immediately or, if patching is not possible, to disable the Git node and restrict access for untrusted users to mitigate risk.
The disclosure follows a series of critical vulnerabilities in n8n, highlighting ongoing security challenges for the platform. The Canadian Centre for Cyber Security and other sources have issued advisories urging prompt action to apply the necessary updates. The vulnerability underscores the importance of timely patch management and access control for workflow automation tools, especially those exposed to untrusted users or the internet.
