CVE-2026-34519

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the reason parameter when creating a Response may be able 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/53b35a2f8869c37a133e60bf1a82a1c01642ba2b	Patch
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4	Release Notes
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-mwh4-6h8g-pg8w	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-04-01 21:17

Updated : 2026-06-17 10:39

NVD link : CVE-2026-34519

Mitre link : CVE-2026-34519

CVE.ORG link : CVE-2026-34519

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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