Malware USBStealer

USBStealer is malware that has been used by APT28 since at least 2005 to extract information from air-gapped networks. It does not have the capability to communicate over the Internet and has been used in conjunction with ADVSTORESHELL.


List of techniques used :


id description
T1020 Automated Exfiltration
Adversaries may exfiltrate data, such as sensitive documents, through the use of automated processing after being gathered during Collection. When automated exfiltration is used, other exfiltration techniques likely apply as well to transfer the information out of the network, such as Exfiltration Over C2 Channel and Exfiltration Over Alternative Protocol.
T1025 Data from Removable Media
Adversaries may search connected removable media on computers they have compromised to find files of interest. Sensitive data can be collected from any removable media (optical disk drive, USB memory, etc.) connected to the compromised system prior to Exfiltration. Interactive command shells may be in use, and common functionality within cmd may be used to gather information. Some adversaries may also use Automated Collection on removable media.
T1027.013 Obfuscated Files or Information: Encrypted/Encoded File
Adversaries may encrypt or encode files to obfuscate strings, bytes, and other specific patterns to impede detection. Encrypting and/or encoding file content aims to conceal malicious artifacts within a file used in an intrusion. Many other techniques, such as Software Packing, Steganography, and Embedded Payloads, share this same broad objective. Encrypting and/or encoding files could lead to a lapse in detection of static signatures, only for this malicious content to be revealed (i.e., Deobfuscate/Decode Files or Information) at the time of execution/use. This type of file obfuscation can be applied to many file artifacts present on victim hosts, such as malware log/configuration and payload files. Files can be encrypted with a hardcoded or user-supplied key, as well as otherwise obfuscated using standard encoding/compression schemes such as Base64. The entire content of a file may be obfuscated, or just specific functions or values (such as C2 addresses). Encryption and encoding may also be applied in redundant layers for additional protection. For example, adversaries may abuse password-protected Word documents or self-extracting (SFX) archives as a method of encrypting/encoding a file such as a Phishing payload. These files typically function by attaching the intended archived content to a decompressor stub that is executed when the file is invoked (e.g., User Execution). Adversaries may also abuse file-specific as well as custom encoding schemes. For example, Byte Order Mark (BOM) headers in text files may be abused to manipulate and obfuscate file content until Command and Scripting Interpreter execution.
T1036.005 Masquerading: Match Legitimate Name or Location
Adversaries may match or approximate the name or location of legitimate files or resources when naming/placing them. This is done for the sake of evading defenses and observation. This may be done by placing an executable in a commonly trusted directory (ex: under System32) or giving it the name of a legitimate, trusted program (ex: svchost.exe). In containerized environments, this may also be done by creating a resource in a namespace that matches the naming convention of a container pod or cluster. Alternatively, a file or container image name given may be a close approximation to legitimate programs/images or something innocuous. Adversaries may also use the same icon of the file they are trying to mimic.
T1052.001 Exfiltration Over Physical Medium: Exfiltration over USB
Adversaries may attempt to exfiltrate data over a USB connected physical device. In certain circumstances, such as an air-gapped network compromise, exfiltration could occur via a USB device introduced by a user. The USB device could be used as the final exfiltration point or to hop between otherwise disconnected systems.
T1070.004 Indicator Removal: File Deletion
Adversaries may delete files left behind by the actions of their intrusion activity. Malware, tools, or other non-native files dropped or created on a system by an adversary (ex: Ingress Tool Transfer) may leave traces to indicate to what was done within a network and how. Removal of these files can occur during an intrusion, or as part of a post-intrusion process to minimize the adversary's footprint. There are tools available from the host operating system to perform cleanup, but adversaries may use other tools as well. Examples of built-in Command and Scripting Interpreter functions include del on Windows and rm or unlink on Linux and macOS.
T1070.006 Indicator Removal: Timestomp
Adversaries may modify file time attributes to hide new files or changes to existing files. Timestomping is a technique that modifies the timestamps of a file (the modify, access, create, and change times), often to mimic files that are in the same folder and blend malicious files with legitimate files. Both the `$STANDARD_INFORMATION` (`$SI`) and `$FILE_NAME` (`$FN`) attributes record times in a Master File Table (MFT) file. `$SI` (dates/time stamps) is displayed to the end user, including in the File System view, while `$FN` is dealt with by the kernel. Modifying the `$SI` attribute is the most common method of timestomping because it can be modified at the user level using API calls. `$FN` timestomping, however, typically requires interacting with the system kernel or moving or renaming a file. Adversaries modify timestamps on files so that they do not appear conspicuous to forensic investigators or file analysis tools. In order to evade detections that rely on identifying discrepancies between the `$SI` and `$FN` attributes, adversaries may also engage in “double timestomping” by modifying times on both attributes simultaneously. Timestomping may be used along with file name Masquerading to hide malware and tools.
T1074.001 Data Staged: Local Data Staging
Adversaries may stage collected data in a central location or directory on the local system prior to Exfiltration. Data may be kept in separate files or combined into one file through techniques such as Archive Collected Data. Interactive command shells may be used, and common functionality within cmd and bash may be used to copy data into a staging location. Adversaries may also stage collected data in various available formats/locations of a system, including local storage databases/repositories or the Windows Registry.
T1083 File and Directory Discovery
Adversaries may enumerate files and directories or may search in specific locations of a host or network share for certain information within a file system. Adversaries may use the information from File and Directory Discovery during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions. Many command shell utilities can be used to obtain this information. Examples include dir, tree, ls, find, and locate. Custom tools may also be used to gather file and directory information and interact with the Native API. Adversaries may also leverage a Network Device CLI on network devices to gather file and directory information (e.g. dir, show flash, and/or nvram). Some files and directories may require elevated or specific user permissions to access.
T1091 Replication Through Removable Media
Adversaries may move onto systems, possibly those on disconnected or air-gapped networks, by copying malware to removable media and taking advantage of Autorun features when the media is inserted into a system and executes. In the case of Lateral Movement, this may occur through modification of executable files stored on removable media or by copying malware and renaming it to look like a legitimate file to trick users into executing it on a separate system. In the case of Initial Access, this may occur through manual manipulation of the media, modification of systems used to initially format the media, or modification to the media's firmware itself. Mobile devices may also be used to infect PCs with malware if connected via USB. This infection may be achieved using devices (Android, iOS, etc.) and, in some instances, USB charging cables. For example, when a smartphone is connected to a system, it may appear to be mounted similar to a USB-connected disk drive. If malware that is compatible with the connected system is on the mobile device, the malware could infect the machine (especially if Autorun features are enabled).
T1092 Communication Through Removable Media
Adversaries can perform command and control between compromised hosts on potentially disconnected networks using removable media to transfer commands from system to system. Both systems would need to be compromised, with the likelihood that an Internet-connected system was compromised first and the second through lateral movement by Replication Through Removable Media. Commands and files would be relayed from the disconnected system to the Internet-connected system to which the adversary has direct access.
T1119 Automated Collection
Once established within a system or network, an adversary may use automated techniques for collecting internal data. Methods for performing this technique could include use of a Command and Scripting Interpreter to search for and copy information fitting set criteria such as file type, location, or name at specific time intervals. In cloud-based environments, adversaries may also use cloud APIs, data pipelines, command line interfaces, or extract, transform, and load (ETL) services to automatically collect data. This functionality could also be built into remote access tools. This technique may incorporate use of other techniques such as File and Directory Discovery and Lateral Tool Transfer to identify and move files, as well as Cloud Service Dashboard and Cloud Storage Object Discovery to identify resources in cloud environments.
T1120 Peripheral Device Discovery
Adversaries may attempt to gather information about attached peripheral devices and components connected to a computer system. Peripheral devices could include auxiliary resources that support a variety of functionalities such as keyboards, printers, cameras, smart card readers, or removable storage. The information may be used to enhance their awareness of the system and network environment or may be used for further actions.
T1547.001 Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder
Adversaries may achieve persistence by adding a program to a startup folder or referencing it with a Registry run key. Adding an entry to the "run keys" in the Registry or startup folder will cause the program referenced to be executed when a user logs in. These programs will be executed under the context of the user and will have the account's associated permissions level. The following run keys are created by default on Windows systems: * HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionRun * HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionRunOnce * HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRun * HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRunOnce Run keys may exist under multiple hives. The HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRunOnceEx is also available but is not created by default on Windows Vista and newer. Registry run key entries can reference programs directly or list them as a dependency. For example, it is possible to load a DLL at logon using a "Depend" key with RunOnceEx: reg add HKLMSOFTWAREMicrosoftWindowsCurrentVersionRunOnceEx001Depend /v 1 /d "C:tempevil[.]dll" Placing a program within a startup folder will also cause that program to execute when a user logs in. There is a startup folder location for individual user accounts as well as a system-wide startup folder that will be checked regardless of which user account logs in. The startup folder path for the current user is C:Users\[Username]AppDataRoamingMicrosoftWindowsStart MenuProgramsStartup. The startup folder path for all users is C:ProgramDataMicrosoftWindowsStart MenuProgramsStartUp. The following Registry keys can be used to set startup folder items for persistence: * HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionExplorerUser Shell Folders * HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionExplorerShell Folders * HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionExplorerShell Folders * HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindowsCurrentVersionExplorerUser Shell Folders The following Registry keys can control automatic startup of services during boot: * HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRunServicesOnce * HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionRunServicesOnce * HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionRunServices * HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionRunServices Using policy settings to specify startup programs creates corresponding values in either of two Registry keys: * HKEY_LOCAL_MACHINESoftwareMicrosoftWindowsCurrentVersionPoliciesExplorerRun * HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionPoliciesExplorerRun Programs listed in the load value of the registry key HKEY_CURRENT_USERSoftwareMicrosoftWindows NTCurrentVersionWindows run automatically for the currently logged-on user. By default, the multistring BootExecute value of the registry key HKEY_LOCAL_MACHINESystemCurrentControlSetControlSession Manager is set to autocheck autochk *. This value causes Windows, at startup, to check the file-system integrity of the hard disks if the system has been shut down abnormally. Adversaries can add other programs or processes to this registry value which will automatically launch at boot. Adversaries can use these configuration locations to execute malware, such as remote access tools, to maintain persistence through system reboots. Adversaries may also use Masquerading to make the Registry entries look as if they are associated with legitimate programs.

List of groups using the malware :


id description
G0007 APT28
APT28 is a threat group that has been attributed to Russia's General Staff Main Intelligence Directorate (GRU) 85th Main Special Service Center (GTsSS) military unit 26165. This group has been active since at least 2004. APT28 reportedly compromised the Hillary Clinton campaign, the Democratic National Committee, and the Democratic Congressional Campaign Committee in 2016 in an attempt to interfere with the U.S. presidential election. In 2018, the US indicted five GRU Unit 26165 officers associated with APT28 for cyber operations (including close-access operations) conducted between 2014 and 2018 against the World Anti-Doping Agency (WADA), the US Anti-Doping Agency, a US nuclear facility, the Organization for the Prohibition of Chemical Weapons (OPCW), the Spiez Swiss Chemicals Laboratory, and other organizations. Some of these were conducted with the assistance of GRU Unit 74455, which is also referred to as Sandworm Team.

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