ULTRIX Security Guide for Administrators

This document, the "ULTRIX Security Guide for Administrators" (June 1990), provides comprehensive guidance for system administrators on establishing and maintaining security for ULTRIX systems (Version 4.0 or higher).

It covers the following key areas:

1. Introduction to Computer Security: Defines the role of the security administrator, the purpose of computer security (protecting data, processing power, and legitimate access), and the three main tools: physical access controls, system-enforced access controls, and auditing. It also outlines how to formulate, implement, and re-evaluate a site-specific security policy, including assessing resource value and user trust.
2. Physical Security: Details measures for protecting computer room components (CPUs, disks, consoles) and storage media (tapes, floppy disks) from unauthorized access, theft, or damage. It also addresses securing resources outside the computer room, like terminals and workstations.
3. Controlling System Access & User Accounts: Describes managing user identities (User ID, Group ID, Audit ID) and login procedures. It highlights improvements in the ULTRIX user account system over traditional BSD, including enhanced password management (minimum length, expiration, generation) and discusses different security levels (BSD, UPGRADE, ENHANCED). It provides instructions for adding, updating, and removing user accounts, and for setting up restricted user environments.
4. Tracking Activity (Auditing): Explains the purpose of auditing (deterrence, detection, damage assessment) and introduces the ULTRIX audit subsystem, along with traditional auditing tools. It details how to select and configure events to be logged, read and filter audit reports, and respond to detected security violations or potential intrusions.
5. Protecting the File System: Offers guidelines for securing various files and directories (command files, special files, user account files, log files, network-related files, and configuration files) by setting appropriate ownership, groups, and permissions. It also covers secure practices for mounting file systems and handling potentially unsafe foreign file systems.
6. Protecting Systems in Networks: Provides strategies for securing ULTRIX systems in network environments (LAT, DECnet, TCP/IP). This includes controlling remote access, restricting network features (like disabling FTP, Telnet, TFTP, and remote logins), and managing network-wide user accounts, recommending BIND/Hesiod and Kerberos for enhanced security.
7. Starting and Configuring a Secure System: Describes security considerations for booting the system in single-user and multi-user modes. It outlines the steps for installing and configuring ULTRIX's enhanced security features, including the use of an interactive security setup script (secsetup) to enable trusted path, auditing, and improved login security.

The document emphasizes that a combination of physical, system-enforced, and auditing controls is necessary for effective computer security.