The Mojave 2020-005 Security Update released on September 24th is causing major issues for some users.
I have reported on many security update issues in the past and this one is more serious.
Just a few of the issues caused by this update.
Memory issues - Reports of large increases of memory usage = no free memory and a large amount of compressed memory.
2. Slow boot & High fan speed
3. System slowness / stalling in finder
4. New local user can not be created through Users & Groups.
5. Migration assistant crashes to login window when started.
6. Large amounts of system.log entries - Class asn1SetToken is implemented in both /System/Library/PrivateFrameworks/StoreServices.framework/Versions/A/StoreServices
7. Errors when using tmutil localsnapshot /
8. Error when running softwareupdate -l (not sure if it causes any issues with the softwareupdate binary)
9. System locks up in Desktop & Screen Saver > Screen Saver when trying to select a picture type screen saver.
10. WindowServer Process using 4 times amount of memory. Should be anywhere between 40-125MB after the update it jumps to 400MB
11. cDock 4 - Dock customization app becomes unusable.
12. Menu bar sometimes does not change after switching from applications back to the finder.
I've included workarounds and fixes inside my article. I will also be updating it as more info comes in.
Apple has just released a new supplemental update to fix all the issues!
Hopefully my article will help you answer some deployment questions.