CVE-2023-49081 HIGH

CVE-2023-49081: aiohttp's ClientSession is vulnerable to CRLF injection via version

Vendor Aio-Libs
Product aiohttp
Weakness CWE-20 · Input validation
Published November 30, 2023
Last update November 4, 2025

CVSS base score

7.2/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

What the vulnerability does

01Description

aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. Improper validation made it possible for an attacker to modify the HTTP request (e.g. to insert a new header) or create a new HTTP request if the attacker controls the HTTP version. The vulnerability only occurs if the attacker can control the HTTP version of the request. This issue has been patched in version 3.9.0.

Key dates

02Disclosure timeline

November 30, 2023 CVE published
November 4, 2025 Record updated