Malware Carbanak

Carbanak is a full-featured, remote backdoor used by a group of the same name (Carbanak). It is intended for espionage, data exfiltration, and providing remote access to infected machines.

Platforms : Windows
Version : 1.1
Created : 31 May 2017
Last Modified : 17 August 2023

List of techniques used :

id	description
T1003	OS Credential Dumping Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password. Credentials can be obtained from OS caches, memory, or structures. Credentials can then be used to perform Lateral Movement and access restricted information. Several of the tools mentioned in associated sub-techniques may be used by both adversaries and professional security testers. Additional custom tools likely exist as well.
T1012	Query Registry Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software. The Registry contains a significant amount of information about the operating system, configuration, software, and security. Information can easily be queried using the Reg utility, though other means to access the Registry exist. Some of the information may help adversaries to further their operation within a network. Adversaries may use the information from Query Registry during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions.
T1021.001	Remote Services: Remote Desktop Protocol Adversaries may use Valid Accounts to log into a computer using the Remote Desktop Protocol (RDP). The adversary may then perform actions as the logged-on user. Remote desktop is a common feature in operating systems. It allows a user to log into an interactive session with a system desktop graphical user interface on a remote system. Microsoft refers to its implementation of the Remote Desktop Protocol (RDP) as Remote Desktop Services (RDS). Adversaries may connect to a remote system over RDP/RDS to expand access if the service is enabled and allows access to accounts with known credentials. Adversaries will likely use Credential Access techniques to acquire credentials to use with RDP. Adversaries may also use RDP in conjunction with the Accessibility Features or Terminal Services DLL for Persistence.
T1027	Obfuscated Files or Information Adversaries may attempt to make an executable or file difficult to discover or analyze by encrypting, encoding, or otherwise obfuscating its contents on the system or in transit. This is common behavior that can be used across different platforms and the network to evade defenses. Payloads may be compressed, archived, or encrypted in order to avoid detection. These payloads may be used during Initial Access or later to mitigate detection. Sometimes a user's action may be required to open and Deobfuscate/Decode Files or Information for User Execution. The user may also be required to input a password to open a password protected compressed/encrypted file that was provided by the adversary. Adversaries may also use compressed or archived scripts, such as JavaScript. Portions of files can also be encoded to hide the plain-text strings that would otherwise help defenders with discovery. Payloads may also be split into separate, seemingly benign files that only reveal malicious functionality when reassembled. Adversaries may also abuse Command Obfuscation to obscure commands executed from payloads or directly via Command and Scripting Interpreter. Environment variables, aliases, characters, and other platform/language specific semantics can be used to evade signature based detections and application control mechanisms.
T1030	Data Transfer Size Limits An adversary may exfiltrate data in fixed size chunks instead of whole files or limit packet sizes below certain thresholds. This approach may be used to avoid triggering network data transfer threshold alerts.
T1055.002	Process Injection: Portable Executable Injection Adversaries may inject portable executables (PE) into processes in order to evade process-based defenses as well as possibly elevate privileges. PE injection is a method of executing arbitrary code in the address space of a separate live process. PE injection is commonly performed by copying code (perhaps without a file on disk) into the virtual address space of the target process before invoking it via a new thread. The write can be performed with native Windows API calls such as VirtualAllocEx and WriteProcessMemory, then invoked with CreateRemoteThread or additional code (ex: shellcode). The displacement of the injected code does introduce the additional requirement for functionality to remap memory references. Running code in the context of another process may allow access to the process's memory, system/network resources, and possibly elevated privileges. Execution via PE injection may also evade detection from security products since the execution is masked under a legitimate process.
T1056.001	Input Capture: Keylogging Adversaries may log user keystrokes to intercept credentials as the user types them. Keylogging is likely to be used to acquire credentials for new access opportunities when OS Credential Dumping efforts are not effective, and may require an adversary to intercept keystrokes on a system for a substantial period of time before credentials can be successfully captured. In order to increase the likelihood of capturing credentials quickly, an adversary may also perform actions such as clearing browser cookies to force users to reauthenticate to systems. Keylogging is the most prevalent type of input capture, with many different ways of intercepting keystrokes. Some methods include: * Hooking API callbacks used for processing keystrokes. Unlike Credential API Hooking, this focuses solely on API functions intended for processing keystroke data. * Reading raw keystroke data from the hardware buffer. * Windows Registry modifications. * Custom drivers. * Modify System Image may provide adversaries with hooks into the operating system of network devices to read raw keystrokes for login sessions.
T1057	Process Discovery Adversaries may attempt to get information about running processes on a system. Information obtained could be used to gain an understanding of common software/applications running on systems within the network. Administrator or otherwise elevated access may provide better process details. Adversaries may use the information from Process Discovery during automated discovery to shape follow-on behaviors, including whether or not the adversary fully infects the target and/or attempts specific actions. In Windows environments, adversaries could obtain details on running processes using the Tasklist utility via cmd or Get-Process via PowerShell. Information about processes can also be extracted from the output of Native API calls such as CreateToolhelp32Snapshot. In Mac and Linux, this is accomplished with the ps command. Adversaries may also opt to enumerate processes via `/proc`. On network devices, Network Device CLI commands such as `show processes` can be used to display current running processes.
T1059.003	Command and Scripting Interpreter: Windows Command Shell Adversaries may abuse the Windows command shell for execution. The Windows command shell (cmd) is the primary command prompt on Windows systems. The Windows command prompt can be used to control almost any aspect of a system, with various permission levels required for different subsets of commands. The command prompt can be invoked remotely via Remote Services such as SSH. Batch files (ex: .bat or .cmd) also provide the shell with a list of sequential commands to run, as well as normal scripting operations such as conditionals and loops. Common uses of batch files include long or repetitive tasks, or the need to run the same set of commands on multiple systems. Adversaries may leverage cmd to execute various commands and payloads. Common uses include cmd to execute a single command, or abusing cmd interactively with input and output forwarded over a command and control channel.
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.
T1071.001	Application Layer Protocol: Web Protocols Adversaries may communicate using application layer protocols associated with web traffic to avoid detection/network filtering by blending in with existing traffic. Commands to the remote system, and often the results of those commands, will be embedded within the protocol traffic between the client and server. Protocols such as HTTP/S and WebSocket that carry web traffic may be very common in environments. HTTP/S packets have many fields and headers in which data can be concealed. An adversary may abuse these protocols to communicate with systems under their control within a victim network while also mimicking normal, expected traffic.
T1113	Screen Capture Adversaries may attempt to take screen captures of the desktop to gather information over the course of an operation. Screen capturing functionality may be included as a feature of a remote access tool used in post-compromise operations. Taking a screenshot is also typically possible through native utilities or API calls, such as CopyFromScreen, xwd, or screencapture.
T1114.001	Email Collection: Local Email Collection Adversaries may target user email on local systems to collect sensitive information. Files containing email data can be acquired from a user’s local system, such as Outlook storage or cache files. Outlook stores data locally in offline data files with an extension of .ost. Outlook 2010 and later supports .ost file sizes up to 50GB, while earlier versions of Outlook support up to 20GB. IMAP accounts in Outlook 2013 (and earlier) and POP accounts use Outlook Data Files (.pst) as opposed to .ost, whereas IMAP accounts in Outlook 2016 (and later) use .ost files. Both types of Outlook data files are typically stored in `C:Users\DocumentsOutlook Files` or `C:Users\AppDataLocalMicrosoftOutlook`.
T1132.001	Data Encoding: Standard Encoding Adversaries may encode data with a standard data encoding system to make the content of command and control traffic more difficult to detect. Command and control (C2) information can be encoded using a standard data encoding system that adheres to existing protocol specifications. Common data encoding schemes include ASCII, Unicode, hexadecimal, Base64, and MIME. Some data encoding systems may also result in data compression, such as gzip.
T1136.001	Create Account: Local Account Adversaries may create a local account to maintain access to victim systems. Local accounts are those configured by an organization for use by users, remote support, services, or for administration on a single system or service. For example, with a sufficient level of access, the Windows net user /add command can be used to create a local account. On macOS systems the dscl -create command can be used to create a local account. Local accounts may also be added to network devices, often via common Network Device CLI commands such as username, or to Kubernetes clusters using the `kubectl` utility. Such accounts may be used to establish secondary credentialed access that do not require persistent remote access tools to be deployed on the system.
T1219	Remote Access Software An adversary may use legitimate desktop support and remote access software to establish an interactive command and control channel to target systems within networks. These services, such as `VNC`, `Team Viewer`, `AnyDesk`, `ScreenConnect`, `LogMein`, `AmmyyAdmin`, and other remote monitoring and management (RMM) tools, are commonly used as legitimate technical support software and may be allowed by application control within a target environment. Remote access software may be installed and used post-compromise as an alternate communications channel for redundant access or as a way to establish an interactive remote desktop session with the target system. They may also be used as a component of malware to establish a reverse connection or back-connect to a service or adversary-controlled system. Adversaries may similarly abuse response features included in EDR and other defensive tools that enable remote access. Installation of many remote access software may also include persistence (e.g., the software's installation routine creates a Windows Service). Remote access modules/features may also exist as part of otherwise existing software (e.g., Google Chrome’s Remote Desktop).
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.
T1573.001	Encrypted Channel: Symmetric Cryptography Adversaries may employ a known symmetric encryption algorithm to conceal command and control traffic rather than relying on any inherent protections provided by a communication protocol. Symmetric encryption algorithms use the same key for plaintext encryption and ciphertext decryption. Common symmetric encryption algorithms include AES, DES, 3DES, Blowfish, and RC4.

List of groups using the malware :

id	description
G0008	Carbanak Carbanak is a cybercriminal group that has used Carbanak malware to target financial institutions since at least 2013. Carbanak may be linked to groups tracked separately as Cobalt Group and FIN7 that have also used Carbanak malware.
G0046	FIN7 FIN7 is a financially-motivated threat group that has been active since 2013. FIN7 has primarily targeted the retail, restaurant, hospitality, software, consulting, financial services, medical equipment, cloud services, media, food and beverage, transportation, and utilities industries in the U.S. A portion of FIN7 was run out of a front company called Combi Security and often used point-of-sale malware for targeting efforts. Since 2020, FIN7 shifted operations to a big game hunting (BGH) approach including use of REvil ransomware and their own Ransomware as a Service (RaaS), Darkside. FIN7 may be linked to the Carbanak Group, but there appears to be several groups using Carbanak malware and are therefore tracked separately.