DNS administrators can use dlint to scan recursively through the domain records of the fully-qualified zone to get a report on any errors therein. You can scan a zone you own, or anyone else's zone on the Internet. dlint talks directly to a primary or secondary nameserver for the zone, to make sure it's working with up-to-date information.
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.