builtins.c in Xinetd before 2.3.15 does not check the service type when the tcpmux-server service is enabled, which exposes all enabled services and allows remote attackers to bypass intended access restrictions via a request to tcpmux port 1.
xinetd 2.3.4 leaks file descriptors for the signal pipe to services that are launched by xinetd, which could allow those services to cause a denial of service via the pipe.