Apple has released an updated version of its XProtect malware defense app to Mac devices running macOS Monterey, Big Sur, and Catalina, Ars Technica reports. Ecletic Light Company's Howard Oakley noted that the new app was significantly more aggressive in malware scanning than the old Malware Removal Tool. Most known Mac malware strains are being scanned by XProtect one or more times daily when user activity is low, with the DubRobber malware being scanned every hour or every two hours, compared with the infrequent execution of MRT, which was often run immediately after device startup. Moreover, Apple has also updated both XProtect and MRT in macOS El Capitan, according to Oakley. "In the last six months, macOS malware protection has changed more than it did over the previous seven years. It has now gone fully preemptive, as active as many commercial anti-malware products, provided that your Mac is running Catalina or later," wrote Oakley.