AA20-239A: FASTCash 2.0: North Korea’s BeagleBoyz Robbing Banks

Cybersecurity and Infrastructure Security Agency (CISA) - Defend Today, Secure Tomorrow

08/26/2020 10:17 AM EDT

 

Original release date: August 26, 2020

Summary

This Alert uses the MITRE Adversarial Tactics, Techniques, and Common Knowledge (ATT&CK®) framework. See the ATT&CK for Enterprise framework for all referenced threat actor techniques.

This joint advisory is the result of analytic efforts among the Cybersecurity and Infrastructure Security Agency (CISA), the Department of the Treasury (Treasury), the Federal Bureau of Investigation (FBI) and U.S. Cyber Command (USCYBERCOM). Working with U.S. government partners, CISA, Treasury, FBI, and USCYBERCOM identified malware and indicators of compromise (IOCs) used by the North Korean government in an automated teller machine (ATM) cash-out scheme—referred to by the U.S. Government as “FASTCash 2.0: North Korea’s BeagleBoyz Robbing Banks.”

CISA, Treasury, FBI, and USCYBERCOM highlight the cyber threat posed by North Korea—formally known as the Democratic People’s Republic of Korea (DPRK)—and provide recommended steps to mitigate the threat.

Refer to the following Malware Analysis Reports for associated IOCs: CROWDEDFLOUNDERECCENTRICBANDWAGONELECTRICFISHFASTCash for WindowsHOPLIGHT, and VIVACIOUSGIFT.

Click here for a PDF version of this report.

!!!WARNING!!!
Since February 2020, North Korea has resumed targeting banks in multiple countries to initiate fraudulent international money transfers and ATM cash outs. The recent resurgence follows a lull in bank targeting since late 2019. This advisory provides an overview of North Korea’s extensive, global cyber-enabled bank robbery scheme, a short profile of the group responsible for this activity, in-depth technical analysis, and detection and mitigation recommendations to counter this ongoing threat to the Financial Services sector.
!!!WARNING!!!

 

Technical Details

North Korea’s intelligence apparatus controls a hacking team dedicated to robbing banks through remote internet access. To differentiate methods from other North Korean malicious cyber activity, the U.S. Government refers to this team as BeagleBoyz, who represent a subset of HIDDEN COBRA activity. The BeagleBoyz overlap to varying degrees with groups tracked by the cybersecurity industry as Lazarus, Advanced Persistent Threat 38 (APT38), Bluenoroff, and Stardust Chollima and are responsible for the FASTCash ATM cash outs reported in October 2018, fraudulent abuse of compromised bank-operated SWIFT system endpoints since at least 2015, and lucrative cryptocurrency thefts. This illicit behavior has been identified by the United Nations (UN) DPRK Panel of Experts as evasion of UN Security Council resolutions, as it generates substantial revenue for North Korea. North Korea can use these funds for its UN-prohibited nuclear weapons and ballistic missile programs. Additionally, this activity poses significant operational risk to the Financial Services sector and erodes the integrity of the financial system.

The BeagleBoyz’s bank robberies pose severe operational risk for individual firms beyond reputational harm and financial loss from theft and recovery costs. The BeagleBoyz have attempted to steal nearly $2 billion since at least 2015, according to public estimates. Equally concerning, these malicious actors have manipulated and, at times, rendered inoperable, critical computer systems at banks and other financial institutions.

  • In 2018, a bank in Africa could not resume normal ATM or point of sale services for its customers for almost two months following an attempted FASTCash incident.
  • The BeagleBoyz often put destructive anti-forensic tools onto computer networks of victim institutions. Additionally, in 2018, they deployed wiper malware against a bank in Chile that crashed thousands of computers and servers to distract from efforts to send fraudulent messages from the bank’s compromised SWIFT terminal.

North Korea’s widespread international bank robbery scheme that exploits critical banking systems may erode confidence in those systems and presents risks to financial institutions across the world. Any BeagleBoyz robbery directed at one bank implicates many other financial services firms in both the theft and the flow of illicit funds back to North Korea. BeagleBoyz activity fits a known North Korean pattern of abusing the international financial system for profit.

  • Fraudulent ATM cash outs have affected upwards of 30 countries in a single incident. The conspirators have withdrawn cash from ATM machines operated by various unwitting banks in multiple countries, including in the United States.
  • The BeagleBoyz also use unwitting banks, including banks in the United States, for their SWIFT fraud scheme. These banks are custodians of accounts belonging to victim banks or unknowingly serve as a pass-through for the fraud. Most infamously, the BeagleBoyz stole $81 million from the Bank of Bangladesh in 2016. The Federal Reserve Bank of New York stopped the remainder of this attempted $1 billion theft after detecting anomalies in the transfer instructions they had received.
FASTCash Update

North Korea’s BeagleBoyz are responsible for the sophisticated cyber-enabled ATM cash-out campaigns identified publicly as “FASTCash” in October 2018. Since 2016, the BeagleBoyz have perpetrated the FASTCash scheme, targeting banks’ retail payment system infrastructure (i.e., switch application servers processing International Standards Organization [ISO] 8583 messages, which is the standard for financial transaction messaging).

Since the publication of the in October 2018, there have been two particularly significant developments in the campaign: (1) the capability to conduct the FASTCash scheme against banks hosting their switch applications on Windows servers, and (2) an expansion of the FASTCash campaign to target interbank payment processors.

  • In October 2018, the U.S. Government identified malware used in the FASTCash scheme that has the capability to manipulate AIX servers running a bank’s switch application to intercept financial request messages and reply with fraudulent, but legitimate-looking, affirmative response messages to enable extensive ATM cash outs. The U.S. Government has since identified functionally equivalent malware for the Windows operating system. Please see the Technical Analysis section below for more information about the ISO 8583 malware for Windows.
  • The BeagleBoyz initially targeted switch applications at individual banks with FASTCash malware but, more recently, have targeted at least two regional interbank payment processors. This suggests the BeagleBoyz are exploring upstream opportunities in the payments ecosystem.

For more information about FASTCash, please see https://www.us-cert.gov/ncas/alerts/TA18-275A.

BEAGLEBOYZ Profile

The BeagleBoyz, an element of the North Korean government’s Reconnaissance General Bureau, have likely been active since at least 2014. As opposed to typical cybercrime, the group likely conducts well-planned, disciplined, and methodical cyber operations more akin to careful espionage activities. Their malicious cyber operations have netted hundreds of millions of U.S. dollars and are likely a major source of funding for the North Korean regime. The group has always used a calculated approach, which allows them to sharpen their tactics, techniques, and procedures while evading detection. Over time, their operations have become increasingly complex and destructive. The tools and implants employed by this group are consistently complex and demonstrate a strong focus on effectiveness and operational security.

Community Identifiers

The BeagleBoyz overlap to varying degrees with groups tracked by the cybersecurity industry as: APT38 (FireEye), Bluenoroff (Kaspersky), Lazarus Group (ESTSecurity), and Stardust Chollima (CrowdStrike).

Targeted Nations

The BeagleBoyz likely have targeted financial institutions in the following nations from 2015 through 2020: Argentina, Brazil, Bangladesh, Bosnia and Herzegovina, Bulgaria, Chile, Costa Rica, Ecuador, Ghana, India, Indonesia, Japan, Jordan, Kenya, Kuwait, Malaysia, Malta, Mexico, Mozambique, Nepal, Nicaragua, Nigeria, Pakistan, Panama, Peru, Philippines, Singapore, South Africa, South Korea, Spain, Taiwan, Tanzania, Togo, Turkey, Uganda, Uruguay, Vietnam, Zambia (figure 1).

Figure 1: Nations probably targeted by BeagleBoyz since 2015

Anatomy of a BeagleBoyz Bank Heist

Figure 2 provides a graphical depiction of a BeagleBoyz bank heist. The next section describes in detail the end-to-end actions the BeagleBoyz take to rob financial institutions with a malicious cyber operation.

Figure 2: BeagleBoyz Bank Heist overview

Technical Analysis

The BeagleBoyz use a variety of tools and techniques to gain access to a financial institution’s network, learn the topology to discover key systems, and monetize their access. The technical analysis below represents an amalgamation of multiple known incidents, rather than details of a single operation. These findings are presented to highlight the group’s ability to tailor their techniques to different targets and to adapt their methods over time. Consequently, there is a need for layered mitigations to effectively defend against this activity, as relying solely on network signature detection will not sufficiently protect against North Korea’s BeagleBoyz.

Initial Access

The BeagleBoyz have used a variety of techniques, such as spearphishing and watering holes, to enable initial access into targeted financial institutions. Towards the end of 2018 through 2019 and in early 2020, the BeagleBoyz demonstrated the use of social engineering tactics by carrying out job-application themed phishing attacks using the following publicly available malicious files.

MD5: b484b0dff093f358897486b58266d069
MD5: f34b72471a205c4eee5221ab9a349c55
MD5: 4c26b2d0e5cd3bfe0a3d07c4b85909a4
MD5: 52ec074d8cb8243976963674dd40ffe7
MD5: d1d779314250fab284fd348888c2f955
MD5: 41fd85ff44107e4604db2f00e911a766
MD5: cf733e719e9677ebfbc84a3ab08dd0dc
MD5: 01d397df2a1cf1d4c8e3615b7064856c

The BeagleBoyz may also be working with or contracting out to criminal hacking groups, like TA505, for initial access development. The third party typically uses commodity malware to establish initial access on a victim’s network and then turns over the access to the BeagleBoyz for follow-on exploitation, which may not occur until months later.

The BeagleBoyz have also used the following techniques to gain an initial foothold on a targeted computer network (Initial Access [TA0001]).

  • Email an attachment with malware to a specific individual, company, or industry (Phishing: Spearphishing Attachment [T1566.001])
  • Compromise a website visited by users in specific communities, industries, or regions (Drive-by Compromise [T1189])
  • Exploit a weakness (a bug, glitch, or design vulnerability) in an internet-facing computer system (such as a database or web server) (Exploit Public Facing Application [T1190])
  • Steal the credentials of a specific user or service account to bypass access controls and gain increased privileges (Valid Accounts [T1078])
  • Breach organizations that have access to the intended victim’s organization and exploit their trusted relationship (Trusted Relationship [T1199])
  • Use remote services to initially access and persist within a victim’s network (External Remote Services [T1133])

Execution

The BeagleBoyz selectively exploit victim computer systems after initially compromising a computer connected to a financial institution’s corporate network. After gaining initial access to a financial institution’s corporate network, the BeagleBoyz are selective in which victim systems they further exploit. The BeagleBoyz use a variety of techniques to run their code on local and remote victim systems [Execution [TA0002]).

  • Use command-line interfaces to interact with systems and execute other software (Command and Scripting Interpreter [T1059])
  • Use scripts (e.g., VBScript and PowerShell) to speed up operational tasks, reduce the time required to gain access to critical resources, and bypass process monitoring mechanisms by directly interacting with the operating system (OS) at an Application Programming Interface (API) level instead of calling other programs (Command and Scripting Interpreter: PowerShell [T1059.001], Command and Scripting Interpreter: Visual Basic [T1059.005])
  • Rely upon specific user actions, such as opening a malicious email attachment (User Execution [T1204])
  • Exploit software vulnerabilities to execute code on a system (Exploitation for Client Execution [T1203])
  • Create new services or modify existing services to execute executables, commands, or scripts (System Services: Service Execution [T1569.002])
  • Employ the Windows module loader to load Dynamic Link Libraries (DLLs) from arbitrary local paths or arbitrary Universal Naming Convention (UNC) network paths and execute arbitrary code on a system (Shared Modules [T1129])
  • Use the Windows API to execute arbitrary code on the victim’s system (Native API [T1106])
  • Use a system’s graphical user interface (GUI) to search for information and execute files (Remote Services [T1021])
  • Use the Task Scheduler to run programs at system startup or on a scheduled basis for persistence, conduct remote execution for lateral movement, gain SYSTEM privileges for privilege escalation, or run a process under the context of a specified account (Scheduled Task/Job [T1053])
  • Abuse compiled Hypertext Markup Language (HTML) files (.chm), commonly distributed as part of the Microsoft HTML Help system, to conceal malicious code (Signed Binary Proxy Execution: Compiled HTML File [T1218.001])
  • Abuse Windows rundll32.exe to execute binaries, scripts, and Control Panel Item files (.CPL) and execute code via proxy to avoid triggering security tools (Signed Binary Proxy Execution: Rundl32 [T1218.001])
  • Exploit cron in Linux and launchd in macOS systems to create pre-scheduled and periodic background jobs (Scheduled Task/Job: Cron [T1053.003], Scheduled Task/Job: Launchd [T1053.004])

Persistence

The BeagleBoyz use many techniques to maintain access on compromised networks through system restarts, changed credentials, and other interruptions that could affect their access (Persistence [TA0003]).

  • Add an entry to the “run keys” in the Registry or an executable to the startup folder to execute malware as the user logs in under the context of the user’s associated permissions levels (Boot or Logon Autostart Execution: Registry Run Keys / Startup Folder [T1547.001])
  • Install a new service that can be configured to execute at startup using utilities to interact with services or by directly modifying the Registry (Create or Modify System Process: Windows Service [T1543.003])
  • Compromise an openly accessible web server with a web script (known as web shell) to use the web server as a gateway into a network and to serve as redundant access or persistence mechanism (Server Software Component: Web Shell [T1505.003])
  • Manipulate accounts (e.g., modifying permissions, modifying credentials, adding or changing permission groups, modifying account settings, or modifying how authentication is performed) to maintain access to credentials and certain permission levels within an environment (Account Manipulation [T1098])
  • Steal the credentials of a specific user or service account to bypass access controls and retain access to remote systems and externally available services (Valid Accounts [T1078])
  • Use the Task Scheduler to run programs at system startup or on a scheduled basis for persistence, conduct remote execution for lateral movement, gain SYSTEM privileges for privilege escalation, or run a process under the context of a specified account (Scheduled Task/Job [T1053])
  • Abuse the Windows DLLs search order and programs that ambiguously specify DLLs to gain privilege escalation and persistence (Hijack Execution Flow: DLL Search Order Hijacking [T1056.004])
  • Exploit hooking to load and execute malicious code within the context of another process to mask the execution, allow access to the process’s memory, and, possibly, gain elevated privileges (Input Capture: Credential API Hooking [T1574.001])
  • Use remote services to persist within a victim’s network (External Remote Services [T1133])

Privilege Escalation

The BeagleBoyz often seek access to financial institutions’ systems that have tiered user and system accounts with customized privileges. The BeagleBoyz must overcome these restrictions to access necessary systems, monitor normal user behavior, and install and execute additional malicious tools. To do so, the BeagleBoyz have used the following techniques to gain higher-level permissions on a system or network (Privilege Escalation [TA0004]).

  • Inject code into processes to evade process-based defenses and elevate privileges (Process Injection [T1055])
  • Install a new service that can be configured to execute at startup using utilities to interact with services or by directly modifying the Registry (Create or Modify System Process: Windows Service [T1543.003])
  • Compromise an openly accessible web server with web shell to use the web server as a gateway into a network (Server Software Component: Web Shell [T1505.003])
  • Use the Task Scheduler to run programs at system startup or on a scheduled basis for persistence, conduct remote execution as part of lateral movement, gain SYSTEM privileges for privilege escalation, or run a process under the context of a specified account (Scheduled Task/Job [T1053])
  • Steal the credentials of a specific user or service account to bypass access controls and grant increased privileges (Valid Accounts [T1078])
  • Exploit hooking to load and execute malicious code within the context of another process to mask the execution, allow access to the process’s memory, and, possibly, gain elevated privileges (Input Capture: Credential API Hooking [T1574.001])
  • Perform Sudo (sometimes referred to as “super user do”) caching or use the Soudoers file to elevate privileges in Linux and macOS systems (Abuse Elevation Control Mechanism: Sudo and Sudo Caching [T1548.003])
  • Execute malicious payloads by hijacking the search order used to load DLLs (Hijack Execution Flow: DLL Search Order Hijacking [T1574.001])

Defense Evasion

Throughout their exploitation of a financial institution’s computer network, the BeagleBoyz have used different techniques to avoid detection by OS security features, system and network security software, and system audits (Defense Evasion [TA0005]).

  • Exploit code signing certificates to masquerade malware and tools as legitimate binaries and bypass security policies that allow only signed binaries to execute on a system (Subvert Trust Controls Signing [T1553.002])
  • Remove malware, tools, or other non-native files dropped or created throughout an intrusion to reduce their footprint or as part of the post-intrusion cleanup process (Indicator Removal on Host: File Deletion [T1070.004])
  • Inject code into processes to evade process-based defenses (Process Injection [T1055])
  • Use scripts (such as VBScript and PowerShell) to bypass process monitoring mechanisms by directly interacting with the OS at an API level instead of calling other programs (Command and Scripting Interpreter: PowerShell [T1059.001], Command and Scripting Interpreter: Visual Basic [T1059.005])
  • Attempt to make an executable or file challenging to discover or analyze by encrypting, encoding, or obfuscating its contents on the system or in transit (Obfuscated Files or Information [T1027])
  • Use external previously compromised web services to relay commands to a victim system (Web Service [T1102])
  • Use software packing to change the file signature, bypass signature-based detection, and decompress the executable code in memory (Unsecured Credentials: Private Keys [T1552.004])
  • Use obfuscated files or information to hide intrusion artifacts (Deobfuscate/Decode Files or Information [T1140])
  • Modify the data timestamps (the modify, access, create, and change times fields) to mimic files that are in the same folder, making them appear inconspicuous to forensic analysts or file analysis tools (Indicator Removal on Host: Remove Timestamp [T1070.006])
  • Abuse Windows utilities to implement arbitrary execution commands and subvert detection and mitigation controls (such as Group Policy) that limit or prevent the usage of cmd.exe or file extensions commonly associated with malicious payloads (Indirect Command Execution [T1202])
  • Use various methods to prevent their commands from appearing in logs and clear command history to remove activity traces (Indicator Removal on Host: Clear Command History [T1070.003])
  • Disable security tools to avoid possible detection of tools and events (Impair Defenses: Disable or Modify Tools [T1562.001])
  • Steal the credentials of a specific user or service account to bypass access controls and grant increased privileges (Valid Accounts [T1078])
  • Delete or alter generated artifacts on a host system, including logs and potentially captured files, to remove traces of activity (Indicator Removal on Host: File Deletion [T1070.004])
  • Abuse compiled HTML files (.chm), commonly distributed as part of the Microsoft HTML Help system, to conceal malicious code (Signed Binary Proxy Execution: Compiled HTML File [T1218.001])
  • Prepend a space to all their terminal commands to operate without leaving traces in the HISTCONTROL environment, which is configured to ignore commands that start with a space (Impair Defenses: HISTCONTROL [T1562.003])
  • Modify malware so it has a different signature and re-use it in cases when the group determines it was quarantined (Obfuscated Files or Information: Indicator Removal from Tools [T1027.005])
  • Attempt to block indicators or events typically captured by sensors from being gathered and analyzed (Impair Defenses: Indicator Blocking [T1562.006])
  • Use the Windows DLLs search order and programs that ambiguously specify DLLs to gain privilege escalation and persistence (Hijack Execution Flow: DLL Search Order Hijacking [T1574.001])
  • Manipulate or abuse the attributes or location of an executable (masquerading) to better blend in with the environment and increase the chances of deceiving a security analyst or product (Masquerading [T1036])
  • Exploit rootkits to hide programs, files, network connections, services, drivers, and other system components (Rootkit [T1014])
  • Abuse the Windows rundll32.exe to execute binaries, scripts, and .CPL files, and execute code via proxy to avoid triggering security tools (Signed Binary Proxy Execution: Rundl32 [T1218.001])

Credential Access

The BeagleBoyz may use malware like ECCENTRICBANDWAGON to log key strokes and take screen captures. The U.S. Government has identified some ECCENTRICBANDWAGON samples that have the ability to RC4 encrypt logged data, but the tool has no network functionality. The implant uses specific formatting for logged data and saves the file locally; another tool obtains the logged data. The implant also contains no mechanism for persistence or self-loading and expects a specific configuration file to be present on the system. A full technical report for ECCENTRICBANDWAGON is available at https://us-cert.cisa.gov/northkorea.

The BeagleBoyz may not always need to use custom keyloggers like ECCENTRICBANDWAGON or other tools to obtain credentials from a compromised system. Depending on the victim’s environment, the BeagleBoyz have used the following techniques to steal credentials (Credential Access [TA0006]).

  • Capture user input, such as keylogging (the most prevalent type of input capture), to obtain credentials for valid accounts and information collection (Input Capture [T1056])
  • Obtain account login and password information, generally in the form of a hash or a clear text password, from the operating system and software (OS Credential Dumping [T1056])
  • Gather private keys from compromised systems to authenticate to remote services or decrypt other collected files (Unsecured Credentials: Private Keys [T1552.004])
  • Manipulate default, domain, local, and cloud accounts to maintain access to credentials and certain permission levels within an environment (Account Manipulation [T1098])
  • Abuse hooking to load and execute malicious code within the context of another process to mask the execution, allow access to the process’s memory, and, possibly, gain elevated privileges (Input Capture: Credential API Hooking [T1056.004])
  • Use brute force techniques to attempt account access when passwords are unknown or when password hashes are unavailable (Brute Force [T1110])

Discovery

Once inside a financial institution’s network, the BeagleBoyz appear to seek two specific systems—the SWIFT terminal and the server hosting the institution’s payment switch application. As they progress through a network, they learn about the systems they have accessed in order to map the network and gain access to the two goal systems. To do so, the BeagleBoyz have used the following techniques to gain knowledge about the systems and internal network (Discovery [TA0007]).

  • Attempt to get detailed information about the operating system and hardware, such as version, patches, hotfixes, service packs, and architecture (System Information Discovery [T1082])
  • Enumerate files and directories or search in specific locations of a host or network share for particular information within a file system (File and Directory Discovery [T1083])
  • Get a list of security software, configurations, defensive tools, and sensors installed on the system (Software Discovery: Security Software Discovery [T1518.001])
  • Procure information about running processes on a system to understand standard software running on network systems (Process Discovery [T1057])
  • Identify primary users, currently logged in users, sets of users that commonly use a system, or active or inactive users (System Owner/User Discovery [T1033])
  • Enumerate browser bookmarks to learn more about compromised hosts, reveal personal information about users, and expose details about internal network resources (Browser Bookmark Discovery [T1217])
  • Look for information on network configuration and system settings on compromised systems, or perform remote system discovery (System Network Configuration Discovery [T1016])
  • Interact with the Windows Registry to gather information about the system, configuration, and installed software (Query Registry [T1012])
  • Get a list of open application windows to learn how the system is used or give context to data collected (Application Window Discovery [T1010])
  • Attempt to get a listing of local system or domain accounts in the compromised system (Account Discovery [T1087])
  • Obtain a list of network connections to and from the compromised system or remote system by querying for information over the network (System Network Connections Discovery [T1049])

Lateral Movement

To access a compromised financial institution’s SWIFT terminal and the server hosting the institution’s payment switch application, the BeagleBoyz leverage harvested credentials and take advantage of the accessibility of these critical systems from other systems in the institution’s corporate network. Specifically, the BeagleBoyz have been known to create firewall exemptions on specific ports, including ports 443, 6443, 8443, and 9443. Depending on the conf

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