DefaultPack.EXE

This binary can be downloaded along side multiple software downloads on the Microsoft website. It gets downloaded when the user forgets to uncheck the option to set Bing as the default search provider.

Execute

Can be used to execute stagers, binaries, and other malicious commands.

DefaultPack.EXE /C:"{CMD}"

Use DefaultPack.EXE to execute arbitrary binaries, with added argument support. — MITRE: T1218 — Privileges: User