From customer:
Product: Azure DevOps Server 2019 | Vendor: Microsoft
Download: https://go.microsoft.com/fwlink/?linkid=2041267&clcid=0x409
Patch: https://aka.ms/azdev2019patch
Silent install: Patch -force
Download/Release Notes: https://devblogs.microsoft.com/devops/may-security-release-patches-available-for-azure-devops-server-2019-tfs-2018-3-2-tfs-2018-1-2-tfs-2017-3-1-and-tfs-2015-4-2/