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.

INFO

Published Date :

2025-10-28T20:14:53.655Z

Last Modified :

2025-11-04T17:41:42.316Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2025-62727 vulnerability.

Vendors Products
Encode
  • Starlette
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-62727.

URL Resource
https://github.com/Kludex/starlette/commit/4ea6e22b489ec388d6004cfbca52dd5b147127c5 cve-icon cve-icon cve-icon
https://github.com/Kludex/starlette/commit/69ed26a85956ef4bd0161807eb27abf49be7cd3c cve-icon cve-icon
https://github.com/Kludex/starlette/releases/tag/0.49.1 cve-icon cve-icon
https://github.com/Kludex/starlette/security/advisories/GHSA-7f5h-v6xp-fcq8 cve-icon cve-icon cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2025-62727 cve-icon
https://www.cve.org/CVERecord?id=CVE-2025-62727 cve-icon
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CVSS Vulnerability Scoring System

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