1. Get access to build infrastructure (e.g. via supply chain attack)
2. Inject code in build to export user's passwords to remote server after update is installed
2. Inject code in build to export user's passwords to remote server after update is installed
An offline password manager is updated a few times a year, and will go through OS repository distribution, with verification of the signature for changes. Or you can download the software from the source website and check the signature.