The portmap service is a demon assigning ports dynamically for RPC services such as NIS and NFS. It has weak authentication mechanisms and has the ability to assign a wide range of port services it controls. For this reason, it is very difficult to secure. I need to some explanation how does this entire service works. For the RPCs this is quiet a requirement in most of the case and the same is also not easy to deny. Does it is important to use TCP wrappers to limit the number of networks and hosts with access to the portmap service since it is with any form of authentication.
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