Apple today published Safari version 15.6.1 in order to support the older macOS Big Sur and macOS Catalina operating systems. As per Apple, the update contains a crucial security patch for a WebKit flaw that might result in arbitrary code execution.
Updates for Safari are strongly advised since Apple stated it is aware of a report that the WebKit vulnerability may have been actively exploited.
By the updates for both WebKit and kernel issues, Apple a few days back released macOS Monterey 12.5.1, iOS 15.6.1, and iPadOS 15.6.1. The kernel-related vulnerability has not yet been patched for macOS Big Sur or macOS Catalina, as mentioned by Mr. Macintosh on Twitter, but it is unknown whether those operating systems are affected.