macOS Monterey 12.3.1 Update – Fixes Monitor, Bluetooth & 2 Zero-Day Vulnerabilities!

macOS Monterey 12.3.1 Update (21E258) is now available

UPDATED: 04/01

Apple just released a minor update for macOS Monterey. The 12.3.1 update addresses three bug fixes and two serious zero-day security vulnerabilities. Let’s jump in and find out what’s new in this update.

Quick Summary

1. Bug fixes – 3 software bugs addressed
2. Security Updates – 2 zero-day security vulnerabilities! “Apple is aware of a report that these issues may have been actively exploited.”
3. Full installer and M1 IPSW – UPDATE: Full installer & M1 IPSW file are now available for download.
4. Safari – UPDATE: 15.4 (17613.1.17.1.13) included in the 12.3.1 update. For Big Sur and Catalina Safari 15.4 (16613.1.17.1.13) is available as a separate download.
5. Enterprise Fixes – “Resolves an issue where a software update may become stuck at an Apple logo and progress bar.”
6. 2021 14 & 16″ MacBook Pro 12.3 Update Bricking Issue = “Some 2021 MacBook Pro models cannot update or restore to macOS Monterey 12.3” Could this be the fix for 2021 MacBook Pro owners that failed the 12.3 update after having their logic board replaced?
7. Apple Business Essentials for small businesses announced.

macOS Monterey Patch Notes Summary

• 1. New Features – 0
• 2. Enhancements -0
• 3. Resolved Issues – 3
• 4. Security Fixes – 2
• 5. Enterprise Fixes – 1

Full Apple OS Release list

iOS 📱✅

• iOS 15.4.1 (19E258)
• iPadOS 15.4.1 (19E258)
• tvOS 15.4.1 (19L452)
• audioOS 15.4.1 (19L452)
• watchOS 8.5.1 (19T252)

macOS 💻 ✅

• Monterey 12.3.1 (21E258)
• Big Sur – No update
• Catalina – No update
• Xcode – No Update

Table of Contents

• 1. Apple Links
• 2. Areas of interest for this update
• 3. Undocumented macOS Monterey Update changes & fixes
• 4. Monterey Release History
• 5. macOS Monterey Full Installer.app
• 6. Apple Silicon IPSW Restore file Update
• 7. macOS Monterey Update sizes for Intel and M1
• 8. Apple Silicon M1 Firmware Update
• 9. Intel T2 BridgeOS Update
• 10. Safari Update
• 11. What’s new for enterprise in macOS Monterey
• 12. Security Content of macOS Monterey
• 13. macOS Monterey Release Notes / Patch Notes / Changes

Click “Continue Reading” for the rest of the article.

1. Apple Links

AppleSeed Notes Link = appleseed.apple.com/

Developer Public Link = developer.apple.com/documentation/macos-release-notes

macOS Deployment References Changes – https://support.apple.com/guide/deployment-reference-macos/document-revision-history-apd04dff7069/web

2. Areas of interest for this update

• 1. None

3. Undocumented macOS Monterey changes & fixes

• 1. None

4. Monterey Release History

• 18. Monterey 12.3.1 (21E258) – 3/31/22 – My Release Notes
• 17. Monterey 12.3 (21E230) – 3/14/22 – My Release Notes
• 16. Monterey 12.2.1 (21D62) – 2/10/22 – My Release Notes
• 15. Monterey 12.2 (21D49) -1/24/22 – My Release Notes
• 14. Monterey 12.1 (21C52) – 12/13/21 – My Release Notes
• 13. Monterey 12.0.1 Final (21A559) – 10/25/21 – My Release Notes
• 12. Monterey 12.0.1 RC2 (21A559) – 10/21/21 – My Release Notes
• 11. Monterey 12.0.1 RC (21A558) – 10/18/21 – My Release Notes
• 10. Monterey Beta 10 (21A5552a) – 10/13/21 – My Release Notes
• 9. Monterey Beta 9 (21A5543b) – 10/06/21 – My Release Notes
• 8. Monterey Beta 8 (21A5534d) – 9/28/21 – My Release Notes
• 7. Monterey Beta 7 (21A5522h) – 9/21/21 – My Release Notes
• 6. Monterey Beta 6 (21A5506j) – 8/30/21 – My Release Notes
• 5. Monterey Beta 5 (21A5304g) – 8/09/21 – My Release Notes
• 4. Monterey Beta 4 (21A5294g) – 7/27/21 – My Release Notes
• 3. Monterey Beta 3 (21A5284e) – 7/14/21 – My Release Notes
• 2. Monterey Beta 2 (21A5268h) – 6/28/21 – My Release Notes
• 1. Monterey Beta 1 (21A5248p) – 6/07/21 – No Release Notes

5. macOS Monterey Full Installer.app

Apple has released the full installer for macOS Monterey. I list all the of the macOS Monterey Full installers in the link below.

https://mrmacintosh.com/macos-12-monterey-full-installer-database-download-directly-from-apple/

InstallAssistant.pkg = Full download. Installing this package will add the full “Install macOS Monterey.app” to your applications folder.

6. Apple Silicon IPSW Restore file Update

Apple has released the full IPSW restore file of macOS Monterey for Apple Silicon M1 Macs. I keep track of all of them in my Apple Silicon Firmware Database

Get them here –> https://mrmacintosh.com/apple-silicon-m1-full-macos-restore-ipsw-firmware-files-database/

7. macOS Monterey Update sizes for Intel and M1

Monterey Delta Update

The delta update will automatically change in size for exactly what your macOS version needs.

• 1. Delta from macOS Monterey 12.3 (21E230) = 1.3GB
• 2. Delta from macOS Monterey 12.2.1 (21D62) = 4.4GB
• 3. Delta from macOS Monterey 12.2 (21D48) = 4.4GB
• 4. Delta from macOS Monterey 12.1 (21C52) = 4.4GB
• 5. Delta from macOS Monterey 12.0.1 (21A559) = 4.5GB
• 6. Full update size = 11.3 GB

Thank you DhinakG

Monterey Combo Update

The “Combo Update” has been replaced by an automatic sized update. This means if you are updating from an version of monterey, you will get an update that includes only the files that you need.

8. Apple Silicon M1 Firmware Update

This update has a new firmware update. The version number is reported in System Information under “System Firmware Version“

Apple Silicon M1 Firmware – Updated!

• 6. macOS Monterey 12.3.1 = 7459.101.3
• 5.macOS Monterey 12.3 = 7459.101.2
• 4. macOS Monterey 12.2.1 = 7429.81.3
• 3. macOS Monterey 12.2 = 7429.81.3
• 2. macOS Monterey 12.1 = 7429.61.2
• 1. macOS Monterey 12.0.1 = 7429.41.5

9. Intel T2 BridgeOS Update

The Version of BridgeOS for your T2 Security Chip (2018-2020 Intel Macs) was updated.

BridgeOS version – Updated

• 6. macOS Monterey 12.3.1 =19.16.14243
• 5. macOS Monterey 12.3 = 19.16.14242.5.1
• 4. macOS Monterey 12.2.1 = 19.16.10744.0.0 (Same as 12.2)
• 3. macOS Monterey 12.2 = 19.16.10744.0.0
• 2. macOS Monterey 12.1 = 19.16.10647.0.0
• 1. macOS Monterey 12.0.1 = 19.16.10548.0.0

10. Safari Update

The new version of Safar 15 is included in the macOS Monterey update.

Safari = UPDATED!

• 6. macOS Monterey 12.3.1 = 15.4 (17613.1.17.1.13)
• 5. macOS Monterey 12.3 = 15.4 (17613.1.17.1.6)
• 4. macOS Monterey 12.2.1 = 15.3 (17612.4.9.1.8)
• 3. macOS Monterey 12.2 = 15.3 (17612.4.9.1.5)
• 2. macOS Monterey 12.1 = 15.2 (17612.3.6.1.6)
• 1. macOS Monterey 12.0.1 = 15.1 (17612.2.9.1.20)

11. What’s new for Enterprise in macOS Monterey

Enterprise changes in macOS Monterey

• 1. Resolves an issue where a software update may become stuck at an Apple logo and progress bar.

https://support.apple.com/HT212586

12. Security Content of macOS Monterey

macOS Monterey Security Document

Security fixes = 2

https://support.apple.com/kb/HT213220

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

13. macOS Monterey Release Notes

https://developer.apple.com/documentation/macos-release-notes

Overview

macOS Monterey 12.3.1 — Restart Required

macOS Monterey 12.3.1 includes bug fixes and security updates for your Mac.

This update fixes the following issues:

• USB-C or Thunderbolt external display does not turn on when connected to Mac mini (2018) as a second display
• Bluetooth devices, such as game controllers, may disconnect from your Mac after playing audio through some Beats headphones

For information on the security content of Apple software updates, please visit this website: https://support.apple.com/kb/HT201222