Wildcard records
web.wildcard
A wildcard makes every possible subdomain resolve, which hides typos and lets anyone point a plausible-looking hostname at your infrastructure.
A longer write-up of this check has not been published yet. The report itself shows the raw evidence behind every result, which is usually the fastest way to see what was measured.
Run this check on a domain
Wildcard records is one of 49 checks in every report, alongside delegation, mail authentication, TLS and registration.