CVE-2025-62727
HIGHStarlette 0.39.0-0.49.0 - Unauthenticated Denial of Service via HTTP Range Header
Title source: llmExploitation Summary
EIP tracks 1 public exploit for CVE-2025-62727. PoCs published by ch4n3-yoon.
AI-analyzed exploit summary This repository contains a functional PoC for CVE-2025-62727, demonstrating a CPU-heavy Range header parsing vulnerability in Starlette's FileResponse. The exploit sends crafted Range headers to trigger excessive regex processing, leading to a denial-of-service condition.
Description
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.
Exploits (1)
This repository contains a functional PoC for CVE-2025-62727, demonstrating a CPU-heavy Range header parsing vulnerability in Starlette's FileResponse. The exploit sends crafted Range headers to trigger excessive regex processing, leading to a denial-of-service condition.
References (4)
Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H