Network Share Discovery
Networks often contain shared network drives and folders that enable users to access file directories on various systems across a network.
Net can be used to query a remote system for available shared drives using the
net view \remotesystem command. It can also be used to query shared drives on the local system using
Adversaries may look for folders and drives shared on remote systems as a means of identifying sources of information to gather as a precursor for Collection and to identify potential systems of interest for Lateral Movement.
On Mac, locally mounted shares can be viewed with the
df -aH command.
Identify unnecessary system utilities or potentially malicious software that may be used to acquire network share information, and audit and/or block them by using whitelisting  tools, like AppLocker,   or Software Restriction Policies  where appropriate. 
System and network discovery techniques normally occur throughout an operation as an adversary learns the environment. Data and events should not be viewed in isolation, but as part of a chain of behavior that could lead to other activities, such as Lateral Movement, based on the information obtained.
Normal, benign system and network events related to legitimate remote system discovery may be uncommon, depending on the environment and how they are used. Monitor processes and command-line arguments for actions that could be taken to gather system and network information. Remote access tools with built-in features may interact directly with the Windows API to gather information. Information may also be acquired through Windows system management tools such as Windows Management Instrumentation and PowerShell.
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