SystHist is a clean and simple app which tells you all the system and security updates which have been installed on that Mac. Now probes deep into the protected territory to find even silent silent updates, and gives details of all the files updated.
anchor apple generic and identifier "co.eclecticlight.SystHist" and (certificate leaf[field.1.2.840.113635.100.6.1.9] /* exists */ or certificate 1[field.1.2.840.113635.100.6.2.6] /* exists */ and certificate leaf[field.1.2.840.113635.100.6.1.13] /* exists */ and certificate leaf[subject.OU] = QWY4LRW926)