Infostealer
YTStealer
According to Intezer, YTStealer is a malware whose objective is to steal YouTube authentication cookies.
YTStealer is a Windows infostealer.
Background
Intezer reports that YTStealer is malware built to harvest YouTube authentication cookies, behaving much like other stealers. Upon launching, its first action is to run a series of environment checks intended to determine whether it is executing inside an analysis sandbox.
Source: Malpedia (Fraunhofer FKIE).