Adversaries may remove share connections that are no longer useful in order to clean up traces of their operation. Windows shared drive and SMB/Windows Admin Shares connections can be removed when no longer needed. Net is an example utility that can be used to remove network share connections with the net use \system\share /delete command. [1]
| ID | Name | Description |
|---|---|---|
| S1159 | DUSTTRAP |
DUSTTRAP can remove network shares from infected systems.[2] |
| S0260 | InvisiMole |
InvisiMole can disconnect previously connected remote drives.[3] |
| S0039 | Net |
The |
| S0400 | RobbinHood |
RobbinHood disconnects all network shares from the computer with the command |
| G0027 | Threat Group-3390 |
Threat Group-3390 has detached network shares after exfiltrating files, likely to evade detection.[5] |
This type of attack technique cannot be easily mitigated with preventive controls since it is based on the abuse of system features.
| ID | Data Source | Data Component | Detects |
|---|---|---|---|
| DS0017 | Command | Command Execution |
Monitor executed commands and arguments of net use commands associated with establishing and removing remote shares over SMB, including following best practices for detection of Windows Admin Shares. |
| DS0029 | Network Traffic | Network Traffic Content |
Monitoring for SMB traffic between systems may also be captured and decoded to look for related network share session and file transfer activity. |
| DS0009 | Process | Process Creation |
Monitor for newly constructed processes and/or command line execution that can be used to remove network share connections via the net.exe process. Note: Event IDs are for Sysmon (Event ID 1 - process create) and Windows Security Log (Event ID 4688 - a new process has been created). The Analytic is oriented around looking for various methods of removing network shares via the command line, which is otherwise a rare event. Analytic 1- Network Share Connection Removal
|
| DS0002 | User Account | User Account Authentication |
Monitoring for Windows authentication logs are also useful in determining when authenticated network shares are established and by which account, and can be used to correlate network share activity to other events to investigate potentially malicious activity. |