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.
Exploitability
AV:NAC:LPR:NUI:RScope
S:CImpact
C:LI:LA:N6.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NInjection
Other