43.2.3. Securing NIS

43.2.3. Securing NIS

The Network Information Service (NIS) is an RPC service, called ypserv,--> which is used in conjunction with portmap and other related services to distribute maps of usernames, passwords, and other sensitive information to any computer claiming to be within its domain.

An NIS server is comprised of several applications. They include the following:

NIS is somewhat insecure by today's standards. It has no host authentication mechanisms and transmits all of its information over the network unencrypted, including password hashes. As a result, extreme care must be taken when setting up a network that uses NIS. This is further complicated by the fact that the default configuration of NIS is inherently insecure.

It is recommended that anyone planning to implement an NIS server first secure the portmap service as outlined in Section 43.2.2, “Securing Portmap”, then address the following issues, such as network planning.


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