aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. A XSS vulnerability exists on index pages for static file handling. This vulnerability is fixed in 3.9.4. We have always recommended using a reverse proxy server (e.g. nginx) for serving static files. Users following the recommendation are unaffected. Other users can disable `show_index` if unable to upgrade.
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-7gpw-8wmc-pm8g
https://github.com/aio-libs/aiohttp/pull/8319
https://github.com/aio-libs/aiohttp/commit/28335525d1eac015a7e7584137678cbb6ff19397