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.