Adversaries may directly access a volume to bypass file access controls and file system monitoring. Windows allows programs to have direct access to logical volumes. Programs with direct access may read and write files directly from the drive by analyzing file system data structures. This technique may bypass Windows file access controls as well as file system monitoring tools. [1]
Utilities, such as NinjaCopy, exist to perform these actions in PowerShell.[2] Adversaries may also use built-in or third-party utilities (such as vssadmin, wbadmin, and esentutl) to create shadow copies or backups of data from system volumes.[3]
| ID | Name | Description |
|---|---|---|
| S0404 | esentutl |
esentutl can use the Volume Shadow Copy service to copy locked files such as |
| G1015 | Scattered Spider |
Scattered Spider has created volume shadow copies of virtual domain controller disks to extract the |
| ID | Mitigation | Description |
|---|---|---|
| M1040 | Behavior Prevention on Endpoint |
Some endpoint security solutions can be configured to block some types of behaviors related to efforts by an adversary to create backups, such as command execution or preventing API calls to backup related services. |
| M1018 | User Account Management |
Ensure only accounts required to configure and manage backups have the privileges to do so. Monitor these accounts for unauthorized backup activity. |
| ID | Data Source | Data Component | Detects |
|---|---|---|---|
| DS0017 | Command | Command Execution |
Monitor executed commands and arguments that could be taken to copy files from the logical drive and evade common file system protections. Since this technique may also be used through PowerShell, additional logging of PowerShell scripts is recommended. |
| DS0016 | Drive | Drive Access |
Monitor handle opens on volumes that are made by processes to determine when they may be directly collecting data from logical drives. [2] |
| DS0022 | File | File Creation |
Monitor for the creation of volume shadow copy and backup files, especially unexpected and irregular activity (relative to time, user, etc.). |