[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] [Z] U.S. Secret Service (USSS) UDP ( User Datagram Protocol) 2nd 3rd [See also network services] DNS and NFS protocol built on TCP Wrappers support for UDP socket UFS (Unix File System) 2nd ufsdump [See dump program] UIDs (user identifiers) 2nd 3rd 4th 5th [See also SUID programs] for superuser real versus effective 2nd and RPC requests for server process stored in inodes su command and switching temporarily zero [See root account superuser] ulimit command Ultrix 2nd umask 2nd UMNT request UMNTALL request unattended terminals Underground (Dreyfus, Suelette) underscore (_), in hostnames Unicode unintended disclosure and uninterruptable power supply [See UPS] unison program United States federal computer crime laws federal jurisdiction Universal Coordinated Time (UTC) Unix [See also specific operating systems] add-on functionality of current trends deployment environments using free versions of history of 2nd 3rd 4th installing new system kernel [See kernel] mobile versions of open source parts of published resources for secure versions of security and 2nd security policy [See policy, security] servers starting up system database files system software, updating thin-client systems utilities 2nd versions covered in this book versions of Unix domain socket Unix File System [See UFS] The UNIX Programming Environment (Kernighan, Brian; Ritchie, Dennis; Pike, Rob) Unix Support Group (USG) UNIX System Administration Handbook (Nemeth, Evi; Snyder, Garth; Seebass, Scott; Hein, Trent R.) UNIX System Security (Wood, Patrick H. and Kochan, Stephen G.) Unix-to-Unix Copy System (UUCP) unowned files unsecure unshare command upgrades backing out of logging sensitive UPS (uninterruptable power supply) 2nd uptime account urandom device Usenet [See also NNTP] groups, security- related news user reporting security holes on USENIX/SAGE Association User Datagram Protocol [See UDP] user IDs [See UIDs] usermod command -e option -f option -s option usernames aliases for doubling as passwords (Joes) 2nd for superuser switching temporarily users [See also employees ; groups; superuser]2nd accidentally deleting files assigning passwords to auditing equipment access of auditing system activity of authenticating backup errors of effects of obscurity on identifiers for [See UIDs] importing to NIS server 2nd as intruders logging monitoring NIS passwords for nobody 2nd participation in security policy power users security awareness of 2nd 3rd 4th security checklist for 2nd security regarding security threats caused by 2nd sending messages to summarizing filesystem usage by switching temporarily system trusted users command 2nd USG (Unix Support Group) /usr directory [See also /var directory] /usr/adm directory /usr/bin directory /usr/bin/uudecode [See uudecode program] /usr/etc/yp/makedbm program /usr/lib directory /usr/lib/preserve program /usr/lib/sendmail [See sendmail program] /usr/lib/uucp/Devices file /usr/lib/uucp/L-devices file /usr/local/lib directory /usr/sbin/rexecd [See rexec service] /usr/ucb directory USSS (U.S. Secret Service) UTC (Universal Coordinated Time) utilities, Unix security vulnerabilities with standard utimes() system call utmp file 2nd 3rd 4th utmpx file UUCP (Unix-to-Unix Copy System) uucp user uudecode program |