Security Update 2021-006 Released for MacOS Catalina

Sep 23, 2021 - 5 Comments

MacOS Catalina update

Apple has released Security Update 2021-006 for macOS Catalina users.

Security Update 2021-006 Catalina includes important security fixes for macOS Catalina and is recommended to install for all users eligible for that update.

Separately, Apple released iOS 12.5.5 for older iPhone and iPad models with the same security fixes.

Installing Security Update 2021-006 Catalina on Mac

Security Update 2021-006 Catalina is available for Macs running macOS Catalina only.

It is a good idea to backup the Mac before installing any software update.

  1. From the  Apple menu, go to System Preferences and choose “Software Update”
  2. Install ‘Security Update 2021-006 Catalina’ on the Mac

The Mac must reboot to complete installation.

Additionally, Mac users who haven’t yet updated to Safari 15 will find that available for MacOS Catalina as well.

Newer Macs or those choosing to run Big Sur will instead find macOS Big Sur 11.6 as the most recent update available.

Let us know if you have any notable experiences with installing the security update.


Related articles:

Posted by: Paul Horowitz in Mac OS, News


» Comments RSS Feed

  1. Tommy says:

    Don’t install the update!!! It ruined my damn system.. can’t watch any videos on HDD or on a browser. Tried calling support and was left dealing with mindless international MORONS who knew nothing about anything… damn morons

  2. Daniel says:

    Won’t install – it appears to, but the system won’t re-boot. I have to roll the system back using Time Machine. Apple really needs to get their act together. My Mac running Big Sur shows as up to date, but its missing 11.6

  3. Fel says:

    I got stuck with iMac 2017 for almost 12 hours on progress bar, and need to reinstall Catalina using Command R.

  4. Kim says:

    Me too same mac same problem
    Tried The usual tricks nothing Seem to work
    Anybody have a solution ?

  5. Gina says:

    I’ve tried installing this update twice on MacBook Pro 2012. Won’t re-boot…gets stuck on progress bar reboot.

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