PyPI: aiohttp

CVE-2023-49081

Safety vulnerability ID: SFTY-20231130-93316

Safety legacy ID: pyup.io-62582

Affected versions of the `aiohttp` package are vulnerable to Improper Input Validation due to insufficient checks on the HTTP version of incoming requests. The vulnerability arises because the HTTP request handling mechanism does not adequately validate the HTTP version, allowing manipulation if controlled by an attacker. An attacker with the ability to influence the HTTP version can exploit this flaw to inject new headers or craft entirely new HTTP requests, potentially leading to unauthorized actions or data exposure.

Created at: Jun 23, 2026Updated at: Jun 23, 2026

Overview

aiohttp's ClientSession is vulnerable to CRLF injection via version

Advisory

Affected versions of the `aiohttp` package are vulnerable to Improper Input Validation due to insufficient checks on the HTTP version of incoming requests. The vulnerability arises because the HTTP request handling mechanism does not adequately validate the HTTP version, allowing manipulation if controlled by an attacker. An attacker with the ability to influence the HTTP version can exploit this flaw to inject new headers or craft entirely new HTTP requests, potentially leading to unauthorized actions or data exposure.

Affected Package

Affecting aiohttp package, versions>=2.0.0rc1,<3.9.0>=4.0.0a0,<=4.0.0a1

Also affects

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How to Fix

Upgradeaiohttpto3.9.0or higher.

Mitigation and Workarounds

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Vulnerable Functions

Functions linked to known vulnerabilities.

Vulnerable function data is available for Enterprise customers

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Safety

Verified by Safety

Our Cybersecurity Intelligence Team reviewed this vulnerability. We combine public data with our own research to find issues not yet reported to public sources.

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