CVE-2026-21858 PoC — n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling

Source

https://github.com/eduardorossi84/CVE-2026-21858-POC

Associated Vulnerability

Title: n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling (CVE-2026-21858)
Description: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.

Description

A maximum severity vulnerability dubbed "Ni8mare" allows remote, unauthenticated attackers to take control over locally deployed instances of the N8N workflow automation platform.

File Snapshot

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