Hello,
All traditional rootkits should need admin privileges to work, considering
that is their nature - to provide admin access to the intruder. Viruses,
however, and other malware can be installed as a standard user (if they are
designed correctly - I doubt many of the ones out today are), however their
effectiveness will be severely limited - they will only be able to
modify/delete data and settings that are tied specifically to your user
account (i.e. your photos, music, downloaded files, etc) and will be unable
to modify/delete files from other user accounts, system programs, system
settings, installed programs, etc.
Any malware installed as a standard user will be much less nasty and easier
to clean up.
Non-admin programs are not allowed to load drivers.
--
- JB
Microsoft MVP - Windows Shell/User
Windows Vista Support Faq
http://www.jimmah.com/vista/