T1561 - Disk Wipe

Adversaries may wipe or corrupt raw disk data on specific systems or in large numbers in a network to interrupt availability to system and network resources. With direct write access to a disk, adversaries may attempt to overwrite portions of disk data. Adversaries may opt to wipe arbitrary portions of disk data and/or wipe disk structures like the master boot record (MBR). A complete wipe of all disk sectors may be attempted.

To maximize impact on the target organization in operations where network-wide availability interruption is the goal, malware used for wiping disks may have worm-like features to propagate across a network by leveraging additional techniques like Valid Accounts, OS Credential Dumping, and SMB/Windows Admin Shares.(Citation: Novetta Blockbuster Destructive Malware)

On network devices, adversaries may wipe configuration files and other data from the device using Network Device CLI commands such as erase.(Citation: erase_cmd_cisco)

Atomic Tests:

Currently, no tests are available for this technique.

Detection

Look for attempts to read/write to sensitive locations like the partition boot sector, master boot record, disk partition table, or BIOS parameter block/superblock. Monitor for direct access read/write attempts using the \.\ notation.(Citation: Microsoft Sysmon v6 May 2017) Monitor for unusual kernel driver installation activity.

Shield Active Defense

Software Manipulation

Make changes to a system’s software properties and functions to achieve a desired effect.

Software Manipulation allows a defender to alter or replace elements of the operating system, file system, or any other software installed and executed on a system.

Opportunity

There is an opportunity for the defender to observe the adversary and control what they can see, what effects they can have, and/or what data they can access.

Use Case

A defender can modify the functionality of commands that are used to delete files or format drives so they fail when used in a specific manner.

Procedures

Hook the Win32 Sleep() function so that it always performs a Sleep(1) instead of the intended duration. This can increase the speed at which dynamic analysis can be performed when a normal malicious file sleeps for long periods before attempting additional capabilities. Hook the Win32 NetUserChangePassword() and modify it such that the new password is different from the one provided. The data passed into the function is encrypted along with the modified new password, then logged so a defender can get alerted about the change as well as decrypt the new password for use. Alter the output of an adversary’s profiling commands to make newly-built systems look like the operating system was installed months earlier. Alter the output of adversary recon commands to not show important assets, such as a file server containing sensitive data.