CVE-2026-111750 AIOHTTP: Pure-Python parser request smuggling
An attacker can smuggle HTTP requests in AIOHTTP when using the pure Python parser, bypassing intermediary security controls.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-111750?
CVE-2026-111750 is a medium-severity vulnerability in aio-libs aiohttp, published on 19 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-444
Which versions are affected by CVE-2026-111750?
2 open source packages ship an affected version, including aiohttp.
| Package | Affected | Fixed in |
|---|---|---|
aiohttp PyPI | All versions | 3.14.4 |
aiohttp PyPI | All versions | 3.14.4 |
How do I fix CVE-2026-111750?
Upgrade aiohttp to 3.14.4 or later.
Is CVE-2026-111750 being exploited?
There is no known exploitation of CVE-2026-111750 in the wild and no public exploit code.
Sources
Also known as AZL-110695, DEBIAN-CVE-2026-111750, ECHO-b67a-7679-1b63, GHSA-pqxq-w44r-73xw, MINI-33gh-gj3f-7hg6, MINI-vcfv-f876-3mjm and 2 more.