https://wccftech.com/download-macos-big-sur-11-6-4-available-with-security-fixes/

Apple has released macOS Big Sur 11.6.4 for everyone with a compatible Mac for download. The update is available over the air.

If you are currently running macOS Big Sur and refuse to update to Monterey, you have a new update to look forward to - 11.6.4. The update packs security fixes, which is extremely vital for the safe and smooth functioning of your Mac.