Linux version of Solaris Security Toolkit?
 

Does there exist an application that performs a similar function as the Solaris Security Toolkit?

I am trying to audit some RHEL systems and was just wondering if there was an automated tool for this.

I don't think we have a structured effort like that. We have some distro-specific tools and generic tools like Sara, COPS, Bastille-Linux and Tiger. I usually start by copying the baseline (/var/lib/rpm in this case) off-site, make a RCS repo for /etc (nice to be able to revert or diff changes), generate an Aide database (say the RPM db gets b0rked) and start by running Tiger.