TL;DR: Open WebUI builds below v0.1.124 carry CVE-2026-44566 ( GHSA-9pgh-j74g-qj6m ) — an arbitrary file upload / path traversal weakness. In a controlled lab demo against a disposable v0.1.120 container, a traversal write reached outside the uploads directory and overwrote /etc/passwd inside the Docker container, injecting a visible hacked account marker. This is not a reverse shell — it is a file-write-to-anywhere impact. Patch now — upgrade to a fixed release, rebuild images, and lock down upload endpoints. ⚠ Security notice: This post is for defensive awareness only . The demo was run in an isolated lab against a disposable target I own and control. This article contains no payloads, no exploit code, and no tooling for download , and no step-by-step reproduction. Do not test systems you do not own or lack explicit permission to assess. Demo intro — Open WebUI CVE-2026-44566 lab thumbnail Watch the lab demo I recorded a short proof-of-concept walkthrough (English ...