AIOHTTP: Duplicate Host header accepted_CVE-2026-34525

6.3 / 10

MEDIUM

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

Description

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, multiple Host headers were allowed in aiohttp. This issue has been patched in version 3.13.4.

Basic Information

ID CVE-2026-34525

Source GitHub_M

Published Apr 1, 2026 at 20:28

Modified Apr 2, 2026 at 16:24

Affected Product

Vendor aio-libs

Product aiohttp

Version < 3.13.4

Affected Versions aio-libs aiohttp < 3.13.4

CWE Classification

CWE-20 CWE-444

References

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    "published": "2026-04-01T20:28:46.652Z",
    "modified": "2026-04-02T16:24:11.311Z",
    "type": "cve",
    "title": "AIOHTTP: Duplicate Host header accepted",
    "source": "GitHub_M",
    "references": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-c427-h43c-vf67\nhttps://github.com/aio-libs/aiohttp/commit/53e2e6fc58b89c6185be7820bd2c9f40216b3000\nhttps://github.com/aio-libs/aiohttp/commit/e00ca3cca92c465c7913c4beb763a72da9ed8349\nhttps://github.com/aio-libs/aiohttp/releases/tag/v3.13.4",
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