n8n Vulnerable to RCE via Arbitrary File Write

CVE-2026-21877 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

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

Basic information

Type
reviewed
Severity
critical
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2026-01-06 17:48:24 UTC
Updated
2026-01-06 17:48:25 UTC
GitHub reviewed
2026-01-06 17:48:24 UTC

EPSS Score

Score Percentile
14.14% 94.27%

CVSS Scores

Base score Version Severity Vector
10.0 3.1 —
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type Value
GHSA GHSA-v364-rw7m-3263 ↗
CVE CVE-2026-21877 ↗

CWEs

CWE id Name
CWE-434 Unrestricted Upload of File with Dangerous Type

Credits

  • theolelasseux (reporter)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
npm n8n >= 0.123.0, < 1.121.3 1.121.3 —

References

cvelogic Threat Intelligence