CVE-2026-48797
Backpropagate: backprop ui --auth and backprop ui --share do not enforce authentication
En resumen
La interfaz web de Backpropagate afirma tener autenticación mediante los comandos --auth y --share, pero nunca valida credenciales. Cualquiera que alcance el puerto del servidor puede cargar datos, iniciar entrenamientos, exportar modelos e enviar a HuggingFace sin iniciar sesión.
Detalle técnico
La CLI exporta BACKPROPAGATE_UI_AUTH al subprocess de Reflex, pero el backend nunca lo lee; no hay middleware de autenticación ni protecciones de solicitudes implementadas. Un atacante con acceso de red al puerto vinculado puede eludir los controles de seguridad anunciados (CWE-862: Autorización Ausente) e invocar operaciones sensibles como carga de datasets, carga de modelos, orquestación de entrenamientos e integración con Hub sin autenticación.
Resumen generado y traducido por IA a partir de la descripción oficial.
Backpropagate is a Python library for fine-tuning large language models on a single GPU. In versions 1.1.0 and 1.1.1, the optional Reflex web UI exposes a training control plane without authentication: dataset upload, model load, training start/stop, multi-run orchestration, GGUF export, and HuggingFace Hub push. The CLI accepts two operator-facing flags intended as security controls: --auth user:pass — documented as "require HTTP Basic authentication on every request to the UI." and--share — documented as "expose the UI on a public address; requires --auth." When --auth user:pass is passed, the CLI prints Auth: enabled (user: <username>) to confirm to the operator that authentication is active, then exports BACKPROPAGATE_UI_AUTH=user:pass to the subprocess that launches the Reflex backend. The Reflex backend (backpropagate/ui_app/**) never reads BACKPROPAGATE_UI_AUTH. No authentication middleware is registered. No request-level guard runs. No WebSocket upgrade guard runs. Any client that reaches the bound port — local or remote, depending on whether --share is used — has full UI access. An inline comment at backpropagate/cli.py:1217-1218 in the v1.1.0 source documents the gap: "For Phase 1 the variable is exported but Reflex doesn't read it yet." This comment was internal-facing; the user-facing documentation (README, CHANGELOG, SHIP_GATE) advertised the contract as enforced. An attacker who reaches the bound port can read uploaded datasets, trigger arbitrary training runs against any local base models as well as read their paths, trigger HuggingFace Hub pushes and cause disk-fill DoS. This issue has been fixed in version 1.2.0. If developers cannot immediately upgrade to 1.2.0 run backprop ui with no flags so it binds to localhost, use SSH port-forwarding (ssh -L 7860:localhost:7860 <training-host>) instead of --share for remote access, and audit any host previously launched with --share, re-issuing any HF tokens used during those sessions.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N