Hide Artifacts: Run Virtual Instance

Adversaries may carry out malicious operations using a virtual instance to avoid detection. A wide variety of virtualization technologies exist that allow for the emulation of a computer or computing environment. By running malicious code inside of a virtual instance, adversaries can hide artifacts associated with their behavior from security tools that are unable to monitor activity inside the virtual instance. Additionally, depending on the virtual networking implementation (ex: bridged adapter), network traffic generated by the virtual instance can be difficult to trace back to the compromised host as the IP address and hostname might not match known values.[1]

Adversaries may utilize native support for virtualization (ex: Hyper-V) or drop the necessary files to run a virtual instance (ex: VirtualBox binaries). After running a virtual instance, adversaries may create a shared folder between the guest and host with permissions that enable the virtual instance to interact with the host file system.[2]

ID: T1564.006
Sub-technique of:  T1564
Tactic: Defense Evasion
Platforms: Linux, Windows, macOS
Permissions Required: User
Contributors: Janantha Marasinghe; Johann Rehberger; Menachem Shafran, XM Cyber
Version: 1.1
Created: 29 June 2020
Last Modified: 14 October 2021

Procedure Examples

ID Name Description
S0451 LoudMiner

LoudMiner has used QEMU and VirtualBox to run a Tiny Core Linux virtual machine, which runs XMRig and makes connections to the C2 server for updates.[3]

S0449 Maze

Maze operators have used VirtualBox and a Windows 7 virtual machine to run the ransomware; the virtual machine's configuration file mapped the shared network drives of the target company, presumably so Maze can encrypt files on the shared drives as well as the local machine.[4]

S0481 Ragnar Locker

Ragnar Locker has used VirtualBox and a stripped Windows XP virtual machine to run itself. The use of a shared folder specified in the configuration enables Ragnar Locker to encrypt files on the host operating system, including files on any mapped drives.[2]

Mitigations

ID Mitigation Description
M1042 Disable or Remove Feature or Program

Disable Hyper-V if not necessary within a given environment.

M1038 Execution Prevention

Use application control to mitigate installation and use of unapproved virtualization software.

Detection

ID Data Source Data Component
DS0017 Command Command Execution
DS0022 File File Creation
DS0007 Image Image Metadata
DS0009 Process Process Creation
DS0019 Service Service Creation
DS0024 Windows Registry Windows Registry Key Modification

Consider monitoring for files and processes associated with running a virtual instance, such as binary files associated with common virtualization technologies (ex: VirtualBox, VMware, QEMU, Hyper-V). Consider monitoring the size of virtual machines running on the system. Adversaries may create virtual images which are smaller than those of typical virtual machines.[5] Network adapter information may also be helpful in detecting the use of virtual instances.

Consider monitoring for process command-line arguments that may be atypical for benign use of virtualization software. Usage of virtualization binaries or command-line arguments associated with running a silent installation may be especially suspect (ex. -silent, -ignore-reboot), as well as those associated with running a headless (in the background with no UI) virtual instance (ex. VBoxManage startvm $VM --type headless).[5] Similarly, monitoring command line arguments which suppress notifications may highlight potentially malicious activity (ex. VBoxManage.exe setextradata global GUI/SuppressMessages "all").

Monitor for commands which enable hypervisors such as Hyper-V. If virtualization software is installed by the adversary, the Registry may provide detection opportunities. Consider monitoring for Windows Service, with respect to virtualization software.

Benign usage of virtualization technology is common in enterprise environments, data and events should not be viewed in isolation, but as part of a chain of behavior.

References