Apple Releases macOS Catalina 10.15.5 Supplemental Update With Security Fix

Apple today released a supplemental update for macOS Catalina 10.15.5, the fifth update to the macOS Catalina operating system that was released in October 2019. The supplemental update comes a week after the release of the macOS Catalina 10.15.5 update.

macos catalina wallpaper
‌macOS Catalina‌ 10.15.5 is a free update that can be downloaded from the Mac App Store using the Update feature in the System Preferences app. There's also a security update for those running macOS High Sierra.

The first macOS Catalina 10.15.5 update introduced a new Battery Health Management feature designed to extend the overall lifespan of a Mac's battery by reducing the rate of chemical aging. It also included controls to fine-tune the calibration of the Pro Display XDR and an option to control Automatic Prominence in a Group FaceTime call.

The supplemental update focuses on security fixes and Apple says it should be installed by all users.

macOS Catalina 10.15.5 supplemental update provides important security updates and is recommended for all users.

Some features may not be available for all regions, or on all Apple devices. For detailed information about the security content of this update, please visit: https://support.apple.com/en-us/HT211215

According to the security notes for the update, it addresses a security flaw that could allow an application to execute arbitrary code with kernel privileges.

This is the same vulnerability that has been addressed in today's iOS 13.5.1, tvOS 13.4.6, and watchOS 6.2.6 updates, and it allowed for the unc0ver jailbreak that allegedly works on all versions of iOS, including iOS 13.5.

Related Forum: macOS Catalina

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Top Rated Comments

FlyGuyDEN Avatar
74 months ago
Seriously-you guys are complaining about security updates? Get a grip.
Score: 19 Votes (Like | Disagree)
Camarillo Brillo Avatar
74 months ago
Great, a security fix, but did they fix any of the broken features in 10.15.4 and 10.15.5 on the 16" MacBook Pro? Probably not.
Score: 14 Votes (Like | Disagree)
filchermcurr Avatar
74 months ago
If anybody is reading this before updating, beware: It will take an eternity to install. Snacks and/or a solid reason to go on living are recommended.

In related news, not too heavy on the firmware this time around. 2018 Mac mini got an iBridge bump and T2 firmware update, neither of which were a monumental jump in version number.
Score: 10 Votes (Like | Disagree)
nwcs Avatar
74 months ago

Apple, getting so tired of this "fxing the fix" bullcr@p. Every single time now, there's always a second patch. Get it right the FIRST time.
Not possible with security related items. It’s always a cat and mouse game and that’s just the way it is.
Score: 9 Votes (Like | Disagree)
jb-net Avatar
74 months ago
Lets take a look at what new bugs Apple introduced this time. The last Catalina updates were horrible. Breaking more things than fixing.
Score: 7 Votes (Like | Disagree)
Rafterman Avatar
74 months ago
Apple, getting so tired of this "fxing the fix" bullcr@p. Every single time now, there's always a second patch. Get it right the FIRST time.
Score: 6 Votes (Like | Disagree)