[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] Hansen, Stephen  hardened system, defined  hardening a system      automated hardening      global versus per-package updates      installing/running only necessary software      keeping software up-to-date      Principle of Least Privilege      principles of      rootkits      Tripwire, and      unnecessary packages          FTP          inetd          linuxconfd, system administration tool          network monitoring          POP          r-services          rpc services          scanning tools          Sendmail          software-development environments          Telnet          X Window System      utilities, Bastille Linux  hash, database format  Hazel, Philip  HEAD method, HTTP  heterogeneous firewall environments  hijacked daemon  HINFO records  honey (decoy) nets  Honeynet Project, information on attackers  host keys  2nd      defined  host-based access control in Apache  host-based IDSes  hosts allow, rsync option  hosts deny, rsync option  Hrycaj, Jordan  HTML, active content tags  htmlentities, PHP function  htmlspecialcharacters, PHP function  HTTP      CGI, and      firewalls, and      methods         GET          HEAD          OPTIONS          POST          PUT  httpd.conf file  2nd  Hunt, Craig  Hybris worm