The kdebase-workspace package consists of what is the desktop for KDE4. The applications and libraries included aren't required to be portable and probably will only work with X11. On other desktops such as OS X and Windows, users wouldn't run these applications, but use the native ones instead. The typical application shouldn't have dependencies in workspace unless they are a component such as a screen-saver or panel applet.
Binary packages can be installed with the high-level tool pkgin (which can be installed with pkg_add) or pkg_add(1) (installed by default). The NetBSD packages collection is also designed to permit easy installation from source.
The pkg_admin audit command locates any installed package which has been mentioned in security advisories as having vulnerabilities.
Please note the vulnerabilities database might not be fully accurate, and not every bug is exploitable with every configuration.
Problem reports, updates or suggestions for this package should be reported with send-pr.