Lateral Tool Transfer
Adversaries may transfer tools or other files between systems in a compromised environment. Files may be copied from one system to another to stage adversary tools or other files over the course of an operation. Adversaries may copy files laterally between internal victim systems to support lateral movement using inherent file sharing protocols such as file sharing over SMB to connected network shares or with authenticated connections with SMB/Windows Admin Shares or Remote Desktop Protocol. Files can also be copied over on Mac and Linux with native tools like scp, rsync, and sftp.
DustySky searches for network drives and removable media and duplicates itself onto them.
LockerGoga has been observed moving around the victim network via SMB, indicating the actors behind this ransomware are manually copying files form computer to computer instead of self-propagating.
|Filter Network Traffic||
Consider using the host firewall to restrict file sharing communications such as SMB. 
|Network Intrusion Prevention||
Network intrusion detection and prevention systems that use network signatures to identify traffic for specific adversary malware or unusual data transfer over known tools and protocols like FTP can be used to mitigate activity at the network level. Signatures are often for unique indicators within protocols and may be based on the specific obfuscation technique used by a particular adversary or tool, and will likely be different across various malware families and versions. 
Monitor for file creation and files transferred within a network using protocols such as SMB. Unusual processes with internal network connections creating files on-system may be suspicious. Consider monitoring for abnormal usage of utilities and command-line arguments that may be used in support of remote transfer of files. Considering monitoring for alike file hashes or characteristics (ex: filename) that are created on multiple hosts.
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