VMware Engineer Confirms macOS Catalina 10.15.6 Bug Causes Crashes with Virtualization

macOS Catalina 10.15.6 seems to have introduced a bug that causes system crashes, especially when using virtualization software such as VirtualBox or VMware.

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Users of virtualization software have reported that macOS 10.15.6 crashes repeatedly when running virtual machines.

A regression in the App Sandbox component of macOS 10.15.6 is reportedly leaking kernel memory, causing macOS to crash. The purpose of an App Sandbox is to provide protection to system resources and limit an app's access to resources, such as memory.

VMware engineers have today diagnosed the issue and filed a "comprehensive" report with Apple, including a minimal reproduction case which should allow them to easily identify and address the issue. The engineer cautions that "it isn't looking good" going forwards, and it will likely fall to Apple to resolve the issue in a software update to macOS. It is unclear if this issue exists in developer and public betas of macOS Big Sur.

The workaround suggested by many users and VMware engineers is to refrain from installing macOS 10.15.6, or shutting down virtual machines when they are not in use and rebooting the host as often as possible.

Tags: macOS, VMware

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Top Rated Comments

73 months ago
Oh Catalina .... even in your final builds you can't give up your reputation....

I really hope the reason for all of the crashes I get on a regular basis coming in and out of sleep, as well as my other reliability issues is because they had their A-team working on the massive Big Sur release for the past few years.... because Catalina has been a terrible experience.
Score: 35 Votes (Like | Disagree)
73 months ago
Still on Mojave. Everything rock stable. Large transfers? OK! VMware? Rock Stable. 32 bit/legacy? Hell yeah. Web browsers? works all the time.
Score: 26 Votes (Like | Disagree)
73 months ago
 is just preparing people for the  Silicon future.
Score: 22 Votes (Like | Disagree)
73 months ago
Good thing I decided to stay on Mojave then.
Score: 21 Votes (Like | Disagree)
ArtOfWarfare Avatar
73 months ago

Question for Mac users, since Catalina has been famously buggy, what's there last best stable MacOS version?
Snow Leopard. Every MacRumors user's favorite $29 update to macOS.
Score: 15 Votes (Like | Disagree)
SaxPlayer Avatar
73 months ago
Parallels Desktop is running fine under Catalina 10.15.6 with an MS Windows VM.
Score: 10 Votes (Like | Disagree)