Security Digest · Vulnerability record
CVE-2026-21877: n8n Vulnerable to RCE via Arbitrary File Write
n8n is an open source workflow automation platform.
CVSS 10.0 Critical EPSS 5.4% · p93
Should you act?
Critical, preconditions apply
Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 5.4%, percentile 93: FIRST’s model estimates a 5.4% chance of exploitation activity in the next 30 days, higher than 93% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes
n8n(npm) >= 0.123.0, < 1.121.3, fixed in 1.121.3. Check your lockfile, including transitive dependencies.
What it is
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.
From the GitHub advisory
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.
Weakness type: CWE-94, CWE-434.
Product: n8n (npm) · Assigned by: GitHub_M · Published: 2026-01-08
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| npm | n8n | >= 0.123.0, < 1.121.3 | 1.121.3 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| n8n-io | n8n | < 1.121.3 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 3.1 | 10 Critical | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| GitHub | 3.1 | 9.9 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: low (any account)
- User interaction: none
- Scope: changed (can affect other components)
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable no, technical impact total.
- FIRST EPSS (model of 2026-10-21): 5.45% probability of exploitation activity in the next 30 days; percentile 93.
Timeline
- — GitHub-reviewed advisory GHSA-v364-rw7m-3263 published (critical)
- — CVE record last updated
- — CVE record published by GitHub_M
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-v364-rw7m-3263 github.com
- CVE.org record CVE-2026-21877 cve.org
- NVD entry CVE-2026-21877 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com