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.
History

Tue, 02 Jun 2026 16:45:00 +0000

Type Values Removed Values Added
First Time appeared Zauberzeug
Zauberzeug nicegui
Vendors & Products Zauberzeug
Zauberzeug nicegui

Tue, 02 Jun 2026 15:45:00 +0000

Type Values Removed Values Added
Description 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.
Title NiceGUI: Unauthenticated log-flood DoS via trailing slash on ESM and per-component resource routes
Weaknesses CWE-248
CWE-770
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-06-02T15:35:07.125Z

Reserved: 2026-05-12T17:48:47.880Z

Link: CVE-2026-45554

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Deferred

Published: 2026-06-02T16:16:41.977

Modified: 2026-06-02T17:15:44.040

Link: CVE-2026-45554

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-06-02T17:00:16Z