CVE-2026-54275

Name	CVE-2026-54275
Description	AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, the server_hostname TLS SNI check can be bypassed when an existing connection is reused. If an application makes multiple requests to the same domain, but with different per-request server_hostname parameters, then the later calls may succeed by reusing the existing connection when they should have been rejected due to the TLS SNI check. This vulnerability is fixed in 3.14.1.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
python-aiohttp (PTS)	bullseye	3.7.4-1	vulnerable
	bullseye (security)	3.7.4-1+deb11u2	vulnerable
	bookworm, bookworm (security)	3.8.4-1+deb12u1	vulnerable
	trixie (security), trixie	3.11.16-1+deb13u1	vulnerable
	forky, sid	3.14.1-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
python-aiohttp	source	(unstable)	3.14.1-1

Notes

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-4m7w-qmgq-4wj5
Fixed by: https://github.com/aio-libs/aiohttp/commit/0ca2b6c28a25726527a8b60f25960262a91ed0e0 (v3.14.1)