CVE-2026-34514

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 v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/aio-libs/aiohttp/commit/9a6ada97e2c6cf1ce31727c6c9fcea17c21f6f06	Patch
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4	Release Notes
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-2vrm-gr82-f7m5	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:*

History

15 Apr 2026, 14:13

Type	Values Removed	Values Added
References	~~() https://github.com/aio-libs/aiohttp/commit/9a6ada97e2c6cf1ce31727c6c9fcea17c21f6f06 -~~	() https://github.com/aio-libs/aiohttp/commit/9a6ada97e2c6cf1ce31727c6c9fcea17c21f6f06 - Patch
References	~~() https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 -~~	() https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 - Release Notes
References	~~() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-2vrm-gr82-f7m5 -~~	() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-2vrm-gr82-f7m5 - Patch, Vendor Advisory
First Time		Aiohttp aiohttp Aiohttp
CPE		cpe:2.3:a:aiohttp:aiohttp::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3

01 Apr 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-01 21:16

Updated : 2026-04-15 14:13

NVD link : CVE-2026-34514

Mitre link : CVE-2026-34514

CVE.ORG link : CVE-2026-34514

JSON object : View

Products Affected

aiohttp

aiohttp

CWE

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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