Vulnerability · Published Oct 19, 2026 · Assigned by GitHub_M

CVE-2026-111748AIOHTTP: Absolute-form request targets can spoof Request.scheme

Medium 6.3

In plain English

A medium-severity security flaw in aiohttp from aio-libs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)6.3Medium

Exploit odds (30 days)0.4%top 67.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	python-aiohttp	no fix listed	DEBIAN-CVE-2026-111748
Debian:13	python-aiohttp	no fix listed	DEBIAN-CVE-2026-111748
Debian:14	python-aiohttp	no fix listed	DEBIAN-CVE-2026-111748
PyPI	aiohttp	3.14.4	GHSA-f9xw-jh8m-3mwq
Ubuntu:26.10	python-aiohttp	no fix listed	UBUNTU-CVE-2026-111748

Affected products (as reported)

Vendor	Product	Versions
aio-libs	aiohttp	< 3.14.4

Weakness: CWE-807 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

References

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-f9xw-jh8m-3mwq x_refsource_CONFIRM
https://github.com/aio-libs/aiohttp/commit/6d4e7b01f9b951aa084a75d7356e907d4ee80411 x_refsource_MISC
https://github.com/aio-libs/aiohttp/releases/tag/v3.14.4 x_refsource_MISC