---
schema_version: '1.0'
id: security-20260711-d9d1cc
url: https://osv.dev/vulnerability/GHSA-mwh4-6h8g-pg8w
url_hash: d9d1ccb612df2ca24520f62c49b681fd97fdb22ccda489ff5aa0388412448544
canonical_url: https://osv.dev/vulnerability/GHSA-mwh4-6h8g-pg8w
source: osv:ghsa
category: security/library
category_raw: cve/library
region: null
tags:
- cve
- CVE-2026-34519
- GHSA-mwh4-6h8g-pg8w
- severity:CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
- aiohttp
- PyPI
lang: en
published_at: '2026-04-01T21:48:24Z'
fetched_at: '2026-07-11T06:37:17Z'
updated_at: '2026-07-11T06:38:28Z'
status: published
content_hash: f5cb9763028c92754b59a2bb114d86d5abebc6c2301b900e392b6d5ffaea666c
license_note: full
summary: AIOHTTP has HTTP response splitting via \r in reason phrase
summary_source: rss
summary_en: AIOHTTP has HTTP response splitting via \r in reason phrase
entities:
- name: HashTag
  type: concept
- name: https://deploymentsafety.openai.com/gpt-5-6/gpt-5-6.pdf
  type: artifact
- name: response.json
  type: artifact
key_facts: []
related: []
related_auto:
- name: SustainableQuantumComputing
  type: concept
  weight: 3.0
title: 'CVE-2026-34519: AIOHTTP has HTTP response splitting via \r in reason phrase'
---

# CVE-2026-34519: AIOHTTP has HTTP response splitting via \r in reason phrase

## TL;DR
AIOHTTP has HTTP response splitting via \r in reason phrase

## Key Points
- cve / CVE-2026-34519 / GHSA-mwh4-6h8g-pg8w / severity:CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U / aiohttp / PyPI

## Details
**Severity:** CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
**Advisory:** GHSA-mwh4-6h8g-pg8w (CVE-2026-34519)

**Affected (your watchlist):**
- `PyPI:aiohttp` 3.13.3 → fixed in 3.13.4 [docker/docker-strands]

**Details:**
### Summary

An attacker who controls the `reason` parameter when creating a `Response` may be able to inject extra headers or similar exploits.

### Impact

In the unlikely situation that an application allows untrusted data to be used in the response's `reason` parameter, then an attacker could manipulate the response to send something different from what the developer intended.

-----

Patch: https://github.com/aio-libs/aiohttp/commit/53b35a2f8869c37a133e60bf1a82a1c01642ba2b

**References:**
- https://github.com/aio-libs/aiohttp/security/advisories/GHSA-mwh4-6h8g-pg8w
- https://nvd.nist.gov/vuln/detail/CVE-2026-34519
- https://github.com/aio-libs/aiohttp/commit/53b35a2f8869c37a133e60bf1a82a1c01642ba2b
- https://github.com/aio-libs/aiohttp
- https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4

_Data: OSV.dev (upstream: ghsa) — https://osv.dev/vulnerability/GHSA-mwh4-6h8g-pg8w_

## Source
元記事: [CVE-2026-34519: AIOHTTP has HTTP response splitting via \r in reason phrase](https://osv.dev/vulnerability/GHSA-mwh4-6h8g-pg8w) — published 2026-04-01T21:48:24Z