The vulnerability of the Application.add_domain() function in the aiohttp HTTP client allows a perpetrator to cause a service failure.

The vulnerability of the Application.adddomain function in the HTTP client of aiohttp is related to the use of duplicate headers due to insufficient validation of input data. Exploiting this vulnerability could allow an attacker to cause service failures...

AIOHTTP accepts duplicate Host headers

Summary Multiple Host headers were allowed in aiohttp. Impact Mostly this doesn't affect aiohttp security itself, but if a reverse proxy is applying security rules depending on the target Host, it is theoretically possible that the proxy and aiohttp could process different host names, possibly...