---
id: CVE-2026-111749
title: >-
  AIOHTTP: Cookie from subdomain can remove Host-Only Scope from existing
  cookies
summary: >-
  AIOHTTP is an asynchronous HTTP client/server framework for asyncio and
  Python. Prior to 3.14.4, Host-Only scope on an existing parent-domain cookie
  can be removed by a subdomain. A user who accesses an untrusted subdomain can
  consequent…
severity: low
cvss: 2.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-565
vendor: aio-libs
product: aiohttp
affected:
  - aiohttp < 3.14.4
published: '2026-10-19'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T17:04:42.374Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-111749'
references:
  - url: >-
      https://github.com/aio-libs/aiohttp/security/advisories/GHSA-gx76-c99x-2c96
    label: >-
      https://github.com/aio-libs/aiohttp/security/advisories/GHSA-gx76-c99x-2c96
  - url: >-
      https://github.com/aio-libs/aiohttp/commit/6a07c171ef9f3be583e2907dcd1931372efca8d6
    label: >-
      https://github.com/aio-libs/aiohttp/commit/6a07c171ef9f3be583e2907dcd1931372efca8d6
  - url: 'https://github.com/aio-libs/aiohttp/releases/tag/v3.14.4'
    label: 'https://github.com/aio-libs/aiohttp/releases/tag/v3.14.4'
tags:
  - cve.org
ingestedAt: '2026-10-19T17:33:42.452Z'
---

## Overview

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, Host-Only scope on an existing parent-domain cookie can be removed by a subdomain. A user who accesses an untrusted subdomain can consequently have host-only protections stripped from cookies, although impact is limited when applications do not reflect those cookies to a browser. This issue is fixed in version 3.14.4.

## Affected

- `aiohttp < 3.14.4`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.