avast! Boot-time scan and Rootkits

[RejZoR]

I was thinking something...
Rootkits are designed to hide files and functions from OS itself.
So even antivirus cannot detect them.
Now if we perform boot-time scan,all OS elements are gone and rootkits are useless.
So avast! has some advantage over other AVs right? Or am i missing something?

[Vlk]

That depends on what kind of rootkits are we talking about. Most of them (but not all) are device drivers, and actually load even before the boot time scanner.

[RejZoR]

I thought you get just basic functionality at boot-time. Looks like it's not that simple...

[Vlk]

At this stage, the device driver can (but necessarily doesn't have to be) loaded. It's more or less its decision at which stage of the boot process to load...