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

15 Apr 2026, 13:54

Type	Values Removed	Values Added
CPE		cpe:2.3:a:aiohttp:aiohttp::::::::
References	~~() https://github.com/aio-libs/aiohttp/commit/cbb774f38330563422ca0c413a71021d7b944145 -~~	() https://github.com/aio-libs/aiohttp/commit/cbb774f38330563422ca0c413a71021d7b944145 - Patch
References	~~() https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 -~~	() https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 - Release Notes
References	~~() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-3wq7-rqq7-wx6j -~~	() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-3wq7-rqq7-wx6j - Patch, Vendor Advisory
First Time		Aiohttp aiohttp Aiohttp
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3

01 Apr 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-01 21:16

Updated : 2026-04-15 13:54

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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