BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to versions 1.4.6, 1.5.2, and 1.6.1, bws_srv_start() in ports/linux/websocket-srv.c builds the libwebsockets server context with a CA certificate loaded but never sets LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT, so the hub accepts TLS connections from clients presenting no certificate at all. Any network-reachable host can join the BACnet/SC mesh without credentials. This issue has been patched in versions 1.4.6, 1.5.2, 1.6.1, and 1.7.0.
CWE-295