CVE-2026-45554 — NiceGUI: Unauthenticated log-flood DoS via trailing slash on ESM and per-component resource routes
NiceGUI is a Python-based UI framework. Prior to version 3.12.0, two FastAPI routes that serve per-component static assets in NiceGUI accept a sub-path parameter that may resolv…
Published: 2026-06-02 · CVSS: 5.3 · CVSS 3.1
NiceGUI is a Python-based UI framework. Prior to version 3.12.0, two FastAPI routes that serve per-component static assets in NiceGUI accept a sub-path parameter that may resolve to a directory rather than a file. Requests that resolve to a directory raise an unhandled RuntimeError inside Starlette's FileResponse, which Uvicorn writes to the server log as a full traceback. Because the routes are reachable without authentication, a remote attacker can amplify log volume and consume disk and log-pipeline capacity on any publicly reachable NiceGUI server. This issue has been patched in version 3.12.0.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7