CVE-2026-21877: n8n is vulnerable to Remote Code Execution via Arbitrary File Write
Impact n8n is affected by an authenticated Remote Code Execution (RCE) vulnerability.
Under certain conditions, an authenticated user may be able to cause untrusted code to be executed by the n8n service. This could result in full compromise of the affected instance.
Both self-hosted and n8n Cloud instances are impacted.
Patches The issue has been resolved in n8n version 1.121.3.
Users are advised to upgrade to this version or later to fully address the vulnerability.
Workarounds If upgrading is not immediately possible, administrators can reduce exposure by disabling the Git node and limiting access for untrusted users.
References - n8n documentation: Blocking access to nodes
Other sources
n8n is an open source workflow automation platform. In versions 0.121.2 and below, an authenticated attacker may be able to execute malicious code using the n8n service. This could result in full compromise and can impact both self-hosted and n8n Cloud instances. This issue is fixed in version 1.121.3. Administrators can reduce exposure by disabling the Git node and limiting access for untrusted users, but upgrading to the latest version is recommended.
— MITRE
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-21877?
CVE-2026-21877 is considered a critical vulnerability due to its potential for authenticated remote code execution.
How do I fix CVE-2026-21877?
To mitigate CVE-2026-21877, upgrade n8n to version 1.121.3 or later.
What type of vulnerability is CVE-2026-21877?
CVE-2026-21877 is an authenticated Remote Code Execution (RCE) vulnerability.
Who is affected by CVE-2026-21877?
Any instance of n8n running versions between 0.123.0 and 1.121.3 is affected by CVE-2026-21877.
What can happen if CVE-2026-21877 is exploited?
Exploitation of CVE-2026-21877 could lead to full compromise of the affected n8n instance.