Malware Analysis Report (AR21-048A)

This report is provided "as is" for informational purposes only. The Department of Homeland Security (DHS) does not provide any warranties of any kind regarding any information contained herein. The DHS does not endorse any commercial product or service referenced in this bulletin or otherwise.

This document is marked TLP:WHITE--Disclosure is not limited. Sources may use TLP:WHITE when information carries minimal or no foreseeable risk of misuse, in accordance with applicable rules and procedures for public release. Subject to standard copyright rules, TLP:WHITE information may be distributed without restriction. For more information on the Traffic Light Protocol (TLP), see http://www.us-cert.gov/tlp.

Description

This Malware Analysis Report (MAR) is the result of analytic efforts among the Federal Bureau of Investigation (FBI), the Cybersecurity and Infrastructure Security Agency (CISA), and the Department of Treasury (Treasury) to highlight the cyber threat to cryptocurrency posed by North Korea, formally known as the Democratic People’s Republic of Korea (DPRK), and provide mitigation recommendations. Working with U.S. government partners, FBI, CISA, and Treasury assess that Lazarus Group—which these agencies attribute to North Korean state-sponsored advanced persistent threat (APT) actors—is targeting individuals and companies, including cryptocurrency exchanges and financial service companies, through the dissemination of cryptocurrency trading applications that have been modified to include malware that facilitates theft of cryptocurrency.

This MAR highlights this cyber threat posed by North Korea and provides detailed indicators of compromise (IOCs) used by the North Korean government. The U.S. Government refers to malicious cyber activity by the North Korean government as HIDDEN COBRA. For more information on other versions of AppleJeus and recommended steps to mitigate this threat, see Joint Cybersecurity Advisory AA21-048A: AppleJeus: Analysis of North Korea's Cryptocurrency Malware at https://www.us-cert.cisa.gov/ncas/alerts/AA21-048A.

There have been multiple versions of AppleJeus malware discovered since its initial discovery in August 2018. In most versions, the malware appears to be from a legitimate-looking cryptocurrency trading company and website, whereby an unsuspecting individual downloads a third-party application from a website that appears legitimate.

The U.S. Government has identified AppleJeus malware version—Celas Trade Pro—and associated IOCs used by the North Korean government in AppleJeus operations.

In August 2018, open source reporting revealed information about a Trojanized version of a legitimate cryptocurrency trading application on a victim’s computer (Note: identity of the victim was not disclosed). The malicious program, known as Celas Trade Pro, is a modified version of the benign QT Bitcoin Trader application. This incident led to the victim company being infected with the malware known to the U.S. Government as FALLCHILL, a North Korean remote administration tool (RAT). According to CISA, FALLCHILL “is a fully functional RAT with multiple commands that the actors can issue from a command and control (C2) server to a victim’s system via dual proxies. FALLCHILL typically infects a system as a file dropped by other HIDDENCOBRA malware. Because of this, additional HIDDENCOBRA malware may be present on systems compromised with FALLCHILL."

Celas Trade Pro had been recommended to the victim company via a phishing email from a company known as Celas Limited. The email provided a link to the Celas Limited website (https://www[.]celasllc.com), where the user could download a Windows or MacOS version of the Celas Trade Pro software.

For a downloadable copy of IOCs, see: MAR-10322463-1.v1.stix.

Submitted Files (6)

5e54bccbd4d93447e79cda0558b0b308a186c2be571c739e5460a3cb6ef665c0 (Updater)

6ee19085ad5c17f989616d17ef68041910b3d0cbcf7e08cc7d7c1a1cb09e6b69 (celastradepro_win_installer_1....)

a84ed8ce714dff76b48b26414de9f045de561146d7eaa09019cbfbb2586c9765 (CelasTradePro.exe)

bdff852398f174e9eef1db1c2d3fefdda25fe0ea90a40a2e06e51b5c0ebd69eb (Updater.exe)

c0c2239138b9bc659b5bddd8f49fa3f3074b65df8f3a2f639f7c632d2306af70 (CelasTradePro)

d404c0a634cef0d32029286fde8efccb6dfe1809066bbec7ac32d42c5ce3bc04 (celastradepro_mac_installer_1....)

Domains (1)

celasllc.com

6ee19085ad5c17f989616d17ef68041910b3d0cbcf7e08cc7d7c1a1cb09e6b69

Tags

droppertrojan

Details

Antivirus

YARA Rules

No matches found.

ssdeep Matches

No matches found.

Relationships

Description

This Windows program from the Celas LLC site is a Windows MSI Installer. The installer looks legitimate and previously had a valid digital signature from Comodo (Sectigo). The signature was signed with a code signing certificate purchased by the same user as the Secure Sockets Layer (SSL) certificate for "celasllc.com." The installer asks for administrative privileges to run and while installing "CelasTradePro.exe" (a84ed8ce714dff76b48b26414de9f045de561146d7eaa09019cbfbb2586c9765) it also installs "Updater.exe" in the “C:\Program Files (x86)\CelasTradePro” folder. Immediately after installation, the installer launches "Updater.exe" (bdff852398f174e9eef1db1c2d3fefdda25fe0ea90a40a2e06e51b5c0ebd69eb) with the “CheckUpdate” parameter.

Screenshots

celasllc.com

Tags

command-and-control

URLs

• celasllc.com/checkupdate.php

Whois

Whois for celasllc.com had the following information in August 2018:
IP Address: 185.142.236.213
Registrant Name: John Broox
Registrant Organization:
Registrant Street: 2141 S Archer Ave
Registrant City: Chicago
Registrant State/Province: Illinois
Registrant Postal Code: 60601
Registrant Country: US
Registrant Phone: +1.8133205751
Registrant Email: johnbroox200@gmail.com
Name server: 1a7ea920.bitcoin-dns.hosting
Name Server: a8332f3a.bitcoin-dns.hosting
Name Server: ad636824.bitcoin-dns.hosting
Name Server: c358ea2d.bitcoin-dns.hosting
Created: May 29, 2018
Expires: May 29, 2019
Updated: Sep 9, 2018

Relationships

Description

The Celas Limited website had a professional appearance, and at the time had a valid Secure Sockets Layer (SSL) certificate issued by Comodo (now Sectigo). The SSL certificate was “Domain Control Validated," which is a weak security verification level for a webserver. Typically, this is a fully automated verification where the certificate requester only needs to demonstrate control over the domain name (i.e. with an email like admin[@]celasllc.com). This type of certificate necessitates no validation of the identity of the website’s owner, nor the existence of the actual business. At the time of analysis, the domain celasllc.com resolved to IP address 185.142.236.213, which belongs to the Netherlands Amsterdam Blackhost Ltd ISP, AS174, Cogent Communications.

Screenshots

a84ed8ce714dff76b48b26414de9f045de561146d7eaa09019cbfbb2586c9765

Tags

trojan

Details

Antivirus

YARA Rules

No matches found.

ssdeep Matches

No matches found.

PE Metadata

PE Sections

Packers/Compilers/Cryptors

Relationships

Description

This file is a 32-bit Windows executable contained within the Windows MSI Installer "celastradepro_win_installer_1.00.00.msi." When executed, "CelasTradePro.exe" asks for the user’s exchange and then loads a legitimate cryptocurrency trading platform with no signs of malicious activity.

CelasTradePro is extremely similar in appearance to a version of an open source cryptocurrency trading platform available around the same timeframe known as QT Bitcoin Trader (screenshots 3 and 4). In addition to similar appearance, many strings found in CelasTradePro have QT Bitcoin Trader references and parameters being set to “Celas Trade Pro” including but not limited to:

--Begin similarities--
String_ABOUT_QT_BITCOIN_TRADER_TEXT=Celas Trade Pro
QtBitcoinTrader
String_ABOUT_QT_BITCOIN_TRADER_TEXT=Celas Trade Pro is a free Open Source project developed on pure C++ Qt and OpenSSL.
julyighor@gmail.com (note: Ighor July is one of the developers of QT Bitcoin Trader)
--End similarities--

The strings also reference the name “John Broox” as the author of CelasTradePro.

While the CelasTradePro application is likely a modification of QT Bitcoin Trader, the legitimate QT Bitcoin Trader for Windows is not available for download as an MSI, but only as a Windows portable executable. This is a singular file named "QtBitcoinTrader.exe" and does not install or run any additional programs. The CelasTradePro MSI contains "CelasTradePro.exe," the modified version of QT Bitcoin Trader, as well as the additional "Updater.exe" (bdff852398f174e9eef1db1c2d3fefdda25fe0ea90a40a2e06e51b5c0ebd69eb) executable not included with the original QT Bitcoin Trader.

Screenshots

bdff852398f174e9eef1db1c2d3fefdda25fe0ea90a40a2e06e51b5c0ebd69eb

Tags

downloaderloaderspywaretrojan

Details

Antivirus

YARA Rules

No matches found.

ssdeep Matches

No matches found.

PE Metadata

PE Sections

Packers/Compilers/Cryptors

Relationships

Description

This file is a 32-bit Windows executable contained within the Windows MSI Installer "celastradepro_win_installer_1.00.00.msi." "Updater.exe" has the same program icon as CelasTradePro. Updater.exe was likely developed under the name “jeus” based on the build path “Z:\jeus\downloader\downloader_exe_vs2010\Release\dloader.pdb” found in the code (partial origin of the name AppleJeus).

"Updater.exe" collects victim host information and sends it back to the server. At launch the malware first checks for the “CheckUpdate” parameter and if not found, exits the program. This is likely to evade detection in a sandbox environment. If the "CheckUpdate" parameter is found, the malware creates a unique identifier for the system following the format “%09d-%05d." It then collects process lists excluding the “System” processes and queries the registry at “HKLM\SOFTWARE\Microsoft\Window NT\CurrentVersion” for the following values:

--Begin values--
ProductName (Windows OS Version)
CurrentBuildNumber (Windows 10 build version)
ReleaseID (Windows 10 version information)
UBR (Sub version of Windows 10 build)
BuildBranch (Windows 10 build branch information)
--End values--

After collecting this information, "Updater.exe" encrypts the data with the hard-coded XOR key “Moz&Wie;#t/6T!2y," prepends the encrypted data with “GIF89a” (image header) and sends the data to "celasllc.com/checkupdate.php."

The malware also uses a hard-coded User-Agent string “Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/6.0” and multipart form data separator “jeus." If the malware receives a response with HTTP code 200, it will decode the base64 payload, then decrypt the result using the hard-coded RC4 decryption key “W29ab@ad%Df324V$Yd." The raw data is then written to a file prepended with the “MAX_PATHjeusD” string.

Screenshots