The Harmony Browse and the SandBlast Agent for Browsers installers must have admin privileges to execute some steps during the installation. Because the MS Installer allows regular users to repair their installation, an attacker running an installer before 90.08.7405 can start the installation repair and place a specially crafted binary in the repair folder, which runs with the admin privileges.
More https://github.com/mandiant/Vulnerability-Disclosures/blob/master/MNDT-2021-0007/MNDT-2021-0007.md
