AIOHTTP: Pure-Python parser request smugglingGHSA-pqxq-w44r-73xw
Fix: aio-libs/aiohttp@9b27347GHSA-pqxq-w44r-73xw is a CWE-444 vulnerability in aiohttp. A fix is available for aiohttp — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
Real-World Exposure
aiohttpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, the pure Python parser accepts ambiguous HTTP request framing. An unauthenticated attacker can consequently smuggle requests when an application uses AIOHTTP_NO_EXTENSIONS or otherwise runs without a standard wheel and an intermediary interprets the framing differently. This issue is fixed in version 3.14.4.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | aiohttp | all versions | 3.14.4pip install --upgrade 'aiohttp==3.14.4' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for aiohttp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update aiohttp to 3.14.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-pqxq-w44r-73xw is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is GHSA-pqxq-w44r-73xw in your dependencies?
Find it across PyPI, including transitive dependencies.