CVE-2026-34517

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, for some multipart form fields, aiohttp read the entire field into memory before checking client_max_size. This issue has been patched in version 3.13.4.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/aio-libs/aiohttp/commit/cbb774f38330563422ca0c413a71021d7b944145	Patch
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4	Release Notes
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-3wq7-rqq7-wx6j	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:*

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) AIOHTTP es un framework cliente/servidor HTTP asíncrono para asyncio y Python. Antes de la versión 3.13.4, para algunos campos de formulario multipart, aiohttp leía el campo completo en la memoria antes de verificar client_max_size. Este problema ha sido parcheado en la versión 3.13.4.

Information

Published : 2026-04-01 21:16

Updated : 2026-10-26 21:10

NVD link : CVE-2026-34517

Mitre link : CVE-2026-34517

CVE.ORG link : CVE-2026-34517

JSON object : View

Products Affected

aiohttp

aiohttp

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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