Improper Certificate Validation vulnerability in the ssl application in Erlang/OTP allows a client that holds a certificate trusted by one SNI virtual host to authenticate to a second SNI virtual host on the same listener by resuming its TLS 1.2 session there. A server that serves several SNI names from one listen socket through sni_fun or sni_hosts keeps one pre-TLS 1.3 session cache per listener and does not bind a cached session to the SNI name or client trust policy that established it. When an SNI option set switches to verify_peer without naming reuse_sessions, ssl_config:update_options