CVE-2026-47265

Name	CVE-2026-47265
Description	AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.14.0, cookies set with the `cookies` parameter on requests are sent after following a cross-origin redirect. If a developer uses the `cookies` parameter on a per-request basis then sensitive data might be leaked to an attacker if they manage to control a redirect. Version 3.14.0 patches the issue. If unable to upgrade, using a `Cookie` header in the `headers` parameter is not vulnerable.
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)
Debian Bugs	1138780

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	3.13.5-1	vulnerable

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)	(unfixed)			1138780

Notes

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-hg6j-4rv6-33pg
https://github.com/aio-libs/aiohttp/commit/f54c40851b0d6c4bbdab97ba518a223adda32478 (v3.14.0)