AIOHTTP: Absolute-form request targets can spoof Request.scheme

MITTEL 6.3CVE-2026-111748 · GHSA-f9xw-jh8m-3mwq · Published 19/10/2026 · updated 19/10/2026

Kurz gesagt

CVE-2026-111748 ist eine Schwachstelle (MITTEL (CVSS 6.3)) in aiohttp.
Wahrscheinlichkeit einer Ausnutzung in den nächsten 30 Tagen (EPSS): 0.39%, höher als bei 32.7% aller Schwachstellen.
Abhilfe: auf 3.14.4 oder neuer aktualisieren.

Package	Affected versions	Patched versions
aiohttp PyPI	`< 3.14.4`	`3.14.4`

Description

Summary

An attacker sending an absolute-form request can spoof the scheme used.

Impact

If user code depends on the Request.scheme attribute for anything security related, an attacker may be able to circumvent this logic, tricking the application into thinking a connection is encrypted when it is not, or vice versa.

Workaround

A WAF rule to reject absolute-form requests (legitimate requests should only use this form for proxies).

NVD description

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, an attacker can send an absolute-form request that causes Request.scheme to use attacker-controlled request-target scheme data instead of the connection protocol. Applications that use Request.scheme for security decisions can consequently be tricked into treating an unencrypted connection as encrypted or an encrypted connection as unencrypted. This issue is fixed in version 3.14.4.