Name: CVE-2026-34514: Improper Neutralization of CRLF Sequences in HTTP Headers
Creator: Rapid7
Published: 2026-04-01T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-34514, CVSS 5.3, EPSS 0.00398

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 Details

CVSS 4.0 Base Score: 2.7 (LOW)
CVSS 4.0 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/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)
CVSS 3.1 Base Score: 5.3
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Alpine Linux	—	Upgrade py3-aiohttp	Apr 29, 2026	Apr 1, 2026
Debian	—	Upgrade python-aiohttp	Jun 2, 2026	Jun 2, 2026
Ubuntu	—	Upgrade python3-aiohttp (Ubuntu Pro)	Jul 23, 2026	Jul 22, 2026

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CVSS Details

Covered by Rapid7

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