CVE-2026-34514HTTP Request/Response Splitting in Aiohttp

Severity
2.7LOWNVD
EPSS
0.0%
top 88.31%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedApr 1

Description

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.

CVSS vector

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

Affected Packages2 packages

PyPIaiohttp/aiohttp< 3.13.4
CVEListV5aio-libs/aiohttp< 3.13.4

🔴Vulnerability Details

4
GHSA
AIOHTTP has CRLF injection through multipart part content type header construction2026-04-01
OSV
CVE-2026-34514: AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python2026-04-01
CVEList
AIOHTTP: CRLF injection in multipart part content type header construction2026-04-01
OSV
AIOHTTP has CRLF injection through multipart part content type header construction2026-04-01

📋Vendor Advisories

2
Red Hat
aiohttp: AIOHTTP: Header Injection via content_type parameter manipulation2026-04-01
Debian
CVE-2026-34514: python-aiohttp - AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. ...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-34514 Impact, Exploitability, and Mitigation Steps | Wiz
CVE-2026-34514 — HTTP Request/Response Splitting | cvebase