CVE-2026-34516 MEDIUM

CVE-2026-34516: AIOHTTP: Multipart Header Size Bypass

Vendor Aio-Libs
Product aiohttp
Weakness CWE-770 · Uncontrolled resource consumption
Published April 1, 2026
Last update April 4, 2026
View on NVD All CVEs

CVSS base score

6.6/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

April 1, 2026 CVE published
April 4, 2026 Record updated