AIOHTTP: Multipart Header Size Bypass_CVE-2026-34516

6.6 / 10

MEDIUM

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

Description

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.

Basic Information

ID CVE-2026-34516

Source GitHub_M

Published Apr 1, 2026 at 20:13

Modified Apr 4, 2026 at 03:11

Affected Product

Vendor aio-libs

Product aiohttp

Version < 3.13.4

Affected Versions aio-libs aiohttp < 3.13.4

CWE Classification

CWE-770

References

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    "published": "2026-04-01T20:13:04.893Z",
    "modified": "2026-04-04T03:11:58.583Z",
    "type": "cve",
    "title": "AIOHTTP: Multipart Header Size Bypass",
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    "references": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-m5qp-6w8w-w647\nhttps://github.com/aio-libs/aiohttp/commit/8a74257b3804c9aac0bf644af93070f68f6c5a6f\nhttps://github.com/aio-libs/aiohttp/releases/tag/v3.13.4",
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