CVE-2026-34516

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, a response with an excessive number of multipart headers may be allowed to use more memory than intended, potentially allowing a DoS vulnerability. This issue has been patched in version 3.13.4.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/aio-libs/aiohttp/commit/8a74257b3804c9aac0bf644af93070f68f6c5a6f	Patch
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4	Release Notes
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-m5qp-6w8w-w647	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

15 Apr 2026, 13:57

Type	Values Removed	Values Added
First Time		Aiohttp aiohttp Aiohttp
CPE		cpe:2.3:a:aiohttp:aiohttp::::::::
References	~~() https://github.com/aio-libs/aiohttp/commit/8a74257b3804c9aac0bf644af93070f68f6c5a6f -~~	() https://github.com/aio-libs/aiohttp/commit/8a74257b3804c9aac0bf644af93070f68f6c5a6f - 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-m5qp-6w8w-w647 -~~	() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-m5qp-6w8w-w647 - Patch, Vendor Advisory

04 Apr 2026, 04:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5

01 Apr 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-01 21:16

Updated : 2026-04-15 13:57

NVD link : CVE-2026-34516

Mitre link : CVE-2026-34516

CVE.ORG link : CVE-2026-34516

JSON object : View

Products Affected

aiohttp

aiohttp

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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