CVE-2025-62727: fallo de gravedad alta en Kludex starlette
Starlette vulnerable to O(n^2) DoS via Range header merging in starlette.responses.FileResponse
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
21Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 7.5epss 0.8%
Starlette is a lightweight ASGI framework/toolkit. Starting in version 0.39.0 and prior to version 0.49.1 , an unauthenticated attacker can send a crafted HTTP Range header that triggers quadratic-time processing in Starlette's FileResponse Range parsing/merging logic. This enables CPU exhaustion per request, causing denial‑of‑service for endpoints serving files (e.g., StaticFiles or any use of FileResponse). This vulnerability is fixed in 0.49.1.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Productos afectados
Kludex · starletteCVEs relacionadas — Kludex starlette
En el mismo producto, de las más peligrosas a las menos.
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Referencias
https://github.com/Kludex/starlette/commit/4ea6e22b489ec388d6004cfbca52dd5b147127c5https://github.com/Kludex/starlette/commit/69ed26a85956ef4bd0161807eb27abf49be7cd3chttps://github.com/Kludex/starlette/releases/tag/0.49.1https://github.com/Kludex/starlette/security/advisories/GHSA-7f5h-v6xp-fcq8