On Monday May 3rd, Apple released important updates to macOS Big Sur, iOS and iPadOS, and watchOS to resolve an issue in WebKit which when "Processing maliciously crafted web content may lead to arbitrary code execution."  Apple has indicated that this issue is being actively exploited. 

Details at https://support.apple.com/en-us/HT201222

The recommendation is to update as soon as reasonable.

-- Rick Wanner MSISE - rwanner at isc dot sans dot edu - Twitter:namedeplume (Protected)