---
id: 10189
title: "The Ni8mare Test: n8n RCE Under the Microscope (CVE-2026-21858)"
cve: CVE-2026-21858
source_domain: horizon3.ai
source_url: "https://horizon3.ai/attack-research/attack-blogs/the-ni8mare-test-n8n-rce-under-the-microscope-cve-2026-21858/"
published_at: "2026-01-08T17:45:57Z"
tags: ["rce", "vulnerability-research"]
phying_url: "https://phying.com/item/10189"
lang: en
---

# The Ni8mare Test: n8n RCE Under the Microscope (CVE-2026-21858)

## Summary

A practical analysis of the Ni8mare n8n vulnerability (CVE-2026-21858), examining real-world exploitability, prerequisites, and why the actual risk is lower than initial reports suggested.

## Intelligence Metadata

- **Sources:** horizon3.ai
- **CVE:** CVE-2026-21858
- **Published:** 2026-01-08T17:45:57Z
- **Original:** https://horizon3.ai/attack-research/attack-blogs/the-ni8mare-test-n8n-rce-under-the-microscope-cve-2026-21858/
- **Phying News:** https://phying.com/item/10189