CVE-2026-21877
n8n Vulnerable to RCE via Arbitrary File Write
Description
### 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](https://docs.n8n.io/hosting/securing/blocking-nodes/)
How to fix CVE-2026-21877
To remediate CVE-2026-21877, upgrade the affected package to a fixed version below.
- —upgrade to 1.121.3 or later
Is CVE-2026-21877 being exploited?
Moderate — EPSS is 5.3%. Track this CVE but it's not at the top of the prioritisation list.
Affected packages (1)
- >= 0.123.0, < 1.121.3
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |