The file is an created by the warez group ElAmigos , intended to update a non-Steam/non-GOG (pirated or offline) copy of Cyberpunk 2077 from game version 2.12 to 2.12 Hotfix (HF) . It does not require an official launcher.
In early 2024, CD Projekt Red released Update 2.12. This was a significant stability patch that addressed several lingering issues from the massive 2.0 overhaul and the Phantom Liberty expansion. However, as is often the case with complex open-world games, the initial 2.12 patch introduced its own set of minor bugs or failed to resolve specific hardware conflicts for some users. CP2077-Update-from-2.12-to-2.12HF-by-ElAmigos.e...
The file is essentially a bridge. It allows a user who has already installed version 2.12 to upgrade to 2.12HF without re-downloading the entire 70GB+ game. It is a technical "diff" file—a collection of changed data that brings the game up to the current standard. The file is an created by the warez