CVE-2025-62727 (GCVE-0-2025-62727)

Vulnerability from cvelistv5 – Published: 2025-10-28 20:14 – Updated: 2025-11-04 17:41
VLAI
Title
Starlette vulnerable to O(n^2) DoS via Range header merging in starlette.responses.FileResponse
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-10-28 20:36 UTC
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7639 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Kludex starlette Affected: >= 0.39.0, < 0.49.1
guessed Create a notification for this product.
Show details on NVD website
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