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Apple releases macOS Catalina 10.15.5 supplemental update with security fixes

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Apple released a supplemental update to macOS Catalina 10.15.5 on Monday afternoon only one week after its official release.

Following an afternoon of updates, Apple's macOS Catalina supplemental update is a simple security update with no special features noted or revealed. The release notes read as follows:

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

The support article Apple referred to stated that a kernel exploit was patched which could allow an application to execute arbitrary code. Apple makes direct reference to the unc0ver exploit that was being used to jailbreak iOS devices in the note.

macOS Catalina 10.15.5 introduced battery health management to the operating system, which first appeared in iPhones and was originally released on 27 May.



9 Comments

melgross 21 Years · 33631 comments

Is there still the problem with creating cloned bootable drives? That’s keeping me from updating to 10.15.5. One backup system I use for my boot drive is to clone it with SuperDuper, which has been very reliable. That also allows incremental updates. Every so often I will wipe that, and do a new bootable clone. This will allow clones created before 10.15.5 to continue to be used, but won’t allow new ones to be created.
The developer of Carbon Copy Cloner, another popular app for this, is concerned that this isn’t an easily fixed bug, as it involves just a couple of small changes, but is a deliberate move by Apple to end the cloning presses altogether. I hope not! But the way Apple has been moving lately has me concerned that it is. The problems I’ve been having with third party preferences panels, which hasn’t been fixed, has me thinking that Apple is closing that area down as well. Not good Apple!.

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Mike Wuerthele 9 Years · 6907 comments

melgross said:
Is there still the problem with creating cloned bootable drives? That’s keeping me from updating to 10.15.5. One backup system I use for my boot drive is to clone it with SuperDuper, which has been very reliable. That also allows incremental updates. Every so often I will wipe that, and do a new bootable clone. This will allow clones created before 10.15.5 to continue to be used, but won’t allow new ones to be created.

The developer of Carbon Copy Cloner, another popular app for this, is concerned that this isn’t an easily fixed bug, as it involves just a couple of small changes, but is a deliberate move by Apple to end the cloning presses altogether. I hope not! But the way Apple has been moving lately has me concerned that it is. The problems I’ve been having with third party preferences panels, which hasn’t been fixed, has me thinking that Apple is closing that area down as well. Not good Apple!.

I think this info is going to take about a day or two to shake out.

ShapeshiftingFish 6 Years · 63 comments

My 2019 13” MacBook Pro has been frequently (like 50% of the time) restarting when waking up from sleep since the update to 10.15.5 couple of days ago (I was waiting for bug reports and felt safe to do it, in hoping it would iron some lingering eGPU issues). Let’s see it this update fixes the new problem. I used to dread only major MacOS updates, now it’s every single one.

gilly33 11 Years · 444 comments

My 2019 13” MacBook Pro has been frequently (like 50% of the time) restarting when waking up from sleep since the update to 10.15.5 couple of days ago (I was waiting for bug reports and felt safe to do it, in hoping it would iron some lingering eGPU issues). Let’s see it this update fixes the new problem. I used to dread only major MacOS updates, now it’s every single one.

I’m having the same problem with my iMac. As a matter of fact since 10.15.4 thought 10.15.5 would solve the problem. Sometimes it shows an icon suggesting there is no bootable drive. Catalina has been a disaster for me. Have a late 2012 machine so it’s upgrade time for sure but still ‘bad Apple’ to borrow from Brian Tong. 

agilealtitude 7 Years · 165 comments

gilly33 said:
My 2019 13” MacBook Pro has been frequently (like 50% of the time) restarting when waking up from sleep since the update to 10.15.5 couple of days ago (I was waiting for bug reports and felt safe to do it, in hoping it would iron some lingering eGPU issues). Let’s see it this update fixes the new problem. I used to dread only major MacOS updates, now it’s every single one.
I’m having the same problem with my iMac. As a matter of fact since 10.15.4 thought 10.15.5 would solve the problem. Sometimes it shows an icon suggesting there is no bootable drive. Catalina has been a disaster for me. Have a late 2012 machine so it’s upgrade time for sure but still ‘bad Apple’ to borrow from Brian Tong. 

Interesting.,.. I was having this issue with 10.15.4, but 10.15.5 seemed to resolve it.  When I do wake the machine up, sometimes I get a washed-out screen.  I need to close the lid and re-open to make it get back to normal.