CVE-2026-69243

Description

A flaw was found in AIOHTTP, an asynchronous HTTP client/server framework. This vulnerability allows a remote attacker to perform HTTP request smuggling due to an edge case in the WebSocket upgrade procedure. When a WebSocket upgrade request includes a body, the parser may switch protocols before the entire body is received. This leaves trailing data to be processed incorrectly, potentially enabling an attacker to bypass security mechanisms or gain unauthorized access to resources.

Statement

Moderate impact. This vulnerability in aiohttp's HTTP parser enables request smuggling when the server-side component handles WebSocket upgrade requests containing a body. An attacker could exploit an edge case during protocol switching, causing trailing data to be processed as subsequent requests or upgraded protocol data. This affects Red Hat products utilizing aiohttp in a server-side capacity.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score7N/AN/A
Attack VectorNetworkN/AN/A
Attack ComplexityHighN/AN/A
Privileges RequiredNoneN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityHighN/AN/A
Integrity ImpactLowN/AN/A
Availability ImpactLowN/AN/A

Vector

Red Hat: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:L

Understanding the Weakness (CWE)

Integrity,Non-Repudiation,Access Control

Technical Impact: Unexpected State; Hide Activities; Bypass Protection Mechanism

An attacker could create HTTP messages to exploit a number of weaknesses including 1) the message can trick the web server to associate a URL with another URL's webpage and caching the contents of the webpage (web cache poisoning attack), 2) the message can be structured to bypass the firewall protection mechanisms and gain unauthorized access to a web application, and 3) the message can invoke a script or a page that returns client credentials (similar to a Cross Site Scripting attack).

Frequently Asked Questions

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