Source: https://msrc.microsoft.com/blog/2023/12/microsoft-addresses-app-installer-abuse/
28 October 2024 Update
Microsoft disabled the ms-appinstaller URI scheme handler by default in App Installer on 28 December 2023 as a security response to protect customers from attackers’ evolving techniques against previous safeguards for CVE-2021-43890.
Microsoft is pleased to announce that we have introduced new safeguards to the ms-appinstaller URI scheme handler by default in version 1.
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