Apple has rolled out macOS Catalina 10.15.7 Supplemental Update, which addresses a variety of security fixes. It can be downloaded by going to System Preferences > Software Update.
This is likely the last major update to macOS Catalina. Today Apple also released a developer beta of macOS Big Sur 11.0.1 to developers. The first (non-beta) public release of the operating system will likely debut along with “Apple Silicon” Macs at next Tuesday’s “One More Thing” event.