Malware associated with Stealth Falcon state-sponsored cyber espionage group uses Windows Background Intelligent Transfer Service (BITS) BITS is a communication protocol in Windows that takes unused network bandwidth to facilitate asynchronous, prioritized, and throttled transfer of files between machines in the foreground or background, without impacting the network experience. After successfully exfiltrating the stolen data, the malware deletes all log and collected files after rewriting them with random data in order to prevent forensic analysis and recovery of the deleted data.
Source: https://thehackernews.com/2019/09/stealthfalcon-virus-windows-bits.html