CVE-2026-111748 AIOHTTP: Absolute-form request targets can spoof Request.scheme
Attackers can spoof request schemes to trick applications into misjudging connection security, bypassing HTTPS enforcement checks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-111748?
CVE-2026-111748 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, an attacker can send an absolute-form request that causes Request.scheme to use attacker-controlled request-target scheme data instead of the connection protocol. Applications that use Request.scheme for security decisions can consequently be tricked into treating an unencrypted connection as encrypted or an encrypted connection as unencrypted. This issue is fixed in version 3.14.4.
Weakness: CWE-807
Which versions are affected by CVE-2026-111748?
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-2026-111748?
Upgrade aiohttp to 3.14.4 or later.
Is CVE-2026-111748 being exploited?
There is no known exploitation of CVE-2026-111748 in the wild and no public exploit code.
Sources
Also known as AZL-110689, CLSA-2026-1793102362, CLSA-2026-1793276744, DEBIAN-CVE-2026-111748, ECHO-a838-5bf3-e286, GHSA-f9xw-jh8m-3mwq and 4 more.