The actual report text identifies the uploaded database as "NUMIDENT".

A quick shufti turned up https://aad.archives.gov/aad/series-description.jsp?s=5057 which states that "NUMIDENT" includes things like "mother's maiden name". Other sources imply that the signatures from SSN application forms (form SS-5) are stored here.

Normal methods of access to this database seem to include "NOVU" (https://catalog.data.gov/dataset/numident-online-verificatio...).