Improper input validation in N8n
CVE-2026-21858
n8n is an open source workflow automation platform. Versions starting with 1.65.0 and below 1.121.0 enable an attacker to access files on the underlying server through execution of certain form-based workflows. A vulnerable workflow could grant access to an unauthenticated remote attacker, resulting in exposure of sensitive information stored on the system and may enable further compromise depending on deployment configuration and workflow usage. This issue is fixed in version 1.121.0.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.782 (99.6th percentile), scored .
High probability of exploitation in the next 30 days — patch promptly. 100th percentile — 99.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.784 · newest: 0.782 · change: -0.003
Affected products
- N8n
- N8n-Io N8n — versions >= 1.65.0, < 1.121.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/n8n-io/n8n/security/advisories/GHSA-v4pr-fm98-w9pg (Vendor Advisory)
- www.cyera.com/research-labs/ni8mare-unauthenticated-remote-code-execution-in-n8… (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-21858?
- CVE-2026-21858 is a critical-severity vulnerability in N8n, classified under Improper Input Validation. CVSS score: 10.0/10. Published 2026-01-08.
- How severe is CVE-2026-21858?
- Critical severity. CVSS v3 base score is 10.0 out of 10.
- Is CVE-2026-21858 known to be exploited?
- 19 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.