Advisories for Golang/Mellium.im/Xmpp package

Impact If no TLS configuration is provided by the user, the websocket package constructs its own TLS configuration using recommended defaults. When looking up a WSS endpoint using the DNS TXT record method described in XEP-0156: Discovering Alternative XMPP Connection Methods the ServerName field was incorrectly being set to the name of the server returned by the TXT record request, not the name of the initial server we were attempting …

If no TLS configuration is provided by the user, the websocket package constructs its own TLS configuration using recommended defaults.

In mellium.im/xmpp, an attacker capable of spoofing DNS TXT records can redirect a WebSocket connection request to a server under their control without causing TLS certificate verification to fail. This occurs because the wrong host name is selected during this verification.