>Hacked code signing certificates seem to be all over the place and Microsoft seems very reluctant to revoke trust out of fear of actually breaking their original customers' software.
AFAIK most (all?) code signing CAs are cracking down on this (or maybe Microsoft is pushing them) by mandating that signing keys be on physical or cloud hosted HSMs. For instance if you try to buy a digicert code signing certificate, all the delivery options are either cloud or physical HSMs.
It's a change to the CA rules that was passed in https://cabforum.org/2022/04/06/ballot-csc-13-update-to-subs... to align OV certificate requirements with the EV ones (that enforces the use of HSMs/hardware tokens/etc) that was meant to go into effect for new certificates issued after November 2022, but was delayed and eventually implemented on June 1 2023.
AFAIK most (all?) code signing CAs are cracking down on this (or maybe Microsoft is pushing them) by mandating that signing keys be on physical or cloud hosted HSMs. For instance if you try to buy a digicert code signing certificate, all the delivery options are either cloud or physical HSMs.
https://www.digicert.com/signing/code-signing-certificates