Malware Analysis – AppleJeus: Dorusio

by | Feb 18, 2021 | Research

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—Dorusio—and associated IOCs used by the North Korean government in AppleJeus operations. Some information has been redacted from this report to preserve victim anonymity.

Dorusio, discovered in March 2020, is a legitimate-looking cryptocurrency trading software that is marketed and distributed by a company and website— Dorusio Wallet and dorusio[.]com, respectively—that appear legitimate. There are Windows and OSX versions of Dorusio Wallet. As of at least early 2020, the actual download links result in 404 errors. The download page has release notes with version revisions claiming to start with Version 1.0.0, which was released on April 15, 2019.

For a downloadable copy of IOCs, see: MAR-10322463-6.v1.stix.

Submitted Files (6)

[Redacted] (dorusio_osx_v2.1.0.dmg)

21afaceee5fab15948a5a724222c948ad17cad181bf514a680267abcce186831 (DorusioUpgrade.exe)

[Redacted] (dorusio_win_v2.1.0.msi)

78b56a1385f2a92f3c9404f71731088646aac6c2c84cc19a449976272dab418f (Dorusio.exe)

a0c461c94ba9f1573c7253666d218b3343d24bfa5d8ef270ee9bc74b7856e492 (Dorusio)

dcb232409c799f6ddfe4bc0566161c2d0b372db6095a0018e6059e34c2b79c61 (dorusio_upgrade)

Domains (1)

dorusio.com

Findings

[Redacted]

Tags

droppertrojan

Details
Name dorusio_win_v2.1.0.msi
Size 141426176 bytes
Type Composite Document File V2 Document, Little Endian, Os: Windows, Version 10.0, MSI Installer, Security: 0, Code page: 1252, Number of Words: 2, Subject: Dorusio, Author: Dorusio Service Ltd, Name of Creating Application: Advanced Installer 14.5.2 build 83143, Template: ;1033, Comments: This installer database contains the logic and data required to install Dorusio., Title: Installation Database, Keywords: Installer, MSI, Database, Number of Pages: 200
MD5 [Redacted]
SHA1 [Redacted]
SHA256 [Redacted]
SHA512 [Redacted]
ssdeep [Redacted]
Entropy [Redacted]
Antivirus

No matches found.

YARA Rules

No matches found.

ssdeep Matches

No matches found.

Relationships
[Redacted] Downloaded_By dorusio.com
[Redacted] Contains 78b56a1385f2a92f3c9404f71731088646aac6c2c84cc19a449976272dab418f
[Redacted] Contains 21afaceee5fab15948a5a724222c948ad17cad181bf514a680267abcce186831
Description

This Windows program from the Dorusio Wallet site is a Windows MSI Installer. This installer appears to be legitimate and will install “Dorusio.exe” (78b56a1385f2a92f3c9404f71731088646aac6c2c84cc19a449976272dab418f) in the “C:\Program Files (x86)\Dorusio” folder. It will also install “DorusioUpgrade.exe” (21afaceee5fab15948a5a724222c948ad17cad181bf514a680267abcce186831) in the “C:\Users\<username>\AppData\Roaming\DorusioSupport” folder. Immediately after installation, the installer launches “DorusioUpgrade.exe.” During installation, a Dorusio folder containing the “Dorusio.exe” application is added to the start menu.

Screenshots

Figure 1 - Screenshot of the Dorusio Wallet installation.

Figure 1 – Screenshot of the Dorusio Wallet installation.

dorusio.com

Tags

command-and-control

URLs
  • dorusio.com/dorusio_update.php
Whois

Whois for dorusio.com had the following information:
Registrar: NAMECHEAP INC
Creation Date: 2020-03-30
Registrar Registration Expiration Date: 2021-03-30

Relationships
dorusio.com Connected_From dcb232409c799f6ddfe4bc0566161c2d0b372db6095a0018e6059e34c2b79c61
dorusio.com Downloaded [Redacted]
dorusio.com Downloaded [Redacted]
Description

The domain “dorusio.com” had a legitimately signed Sectigo SSL certificate, which was “Domain Control Validated” similar to the domain certificates for previous AppleJeus domain certificates. Investigation revealed the point of contact listed for verification was support[@]dorusio.com. No other contact information was available as the administrative or technical contact for the domain.

The domain is registered with NameCheap at the IP address 198.54.115.51 with ASN 22612. This IP is on the same ASN as the AppleJeus version 5 “CoinGoTrade” IP address.

Screenshots

Figure 2 -  Screenshot of the Dorusio site.

Figure 2 – Screenshot of the Dorusio site.

Figure 3 - Screenshot of the Dorusio download page.

Figure 3 – Screenshot of the Dorusio download page.

78b56a1385f2a92f3c9404f71731088646aac6c2c84cc19a449976272dab418f

Tags

trojan

Details
Name Dorusio.exe
Size 97682432 bytes
Type PE32+ executable (GUI) x86-64, for MS Windows
MD5 6c36c8efe2ec2b12f343537d214f45e8
SHA1 69eb27395e8f23b592547b69fbaf19ad03d6a89a
SHA256 78b56a1385f2a92f3c9404f71731088646aac6c2c84cc19a449976272dab418f
SHA512 e9e72322983315d7a99e104b0a36e6301b7c78b3e93fc33c03e2e74ea1d5423b852a23a87a8ecaadf33f73ceb03b306d953b197a13542ae436c6b039ec1c00a7
ssdeep 1572864:odJvugr82jf19dUM/1T8+1VJRukUhkmG:odhg6Pm
Entropy 6.674758
Antivirus

No matches found.

YARA Rules

No matches found.

ssdeep Matches
97 1b60a6d35c872102f535ae6a3d7669fb7d55c43dc7e73354423fdcca01a955d6
PE Metadata
Compile Date 2019-12-16 00:00:00-05:00
Import Hash bb1d46df79ee2045d0bc2529cf6c7458
Company Name BitPay
File Description Dorusio
Internal Name Dorusio
Legal Copyright Copyright © 2020 BitPay
Product Name Dorusio
Product Version 2.1.0.0
PE Sections
MD5 Name Raw Size Entropy
f62420692d3492b34a0696beb92d52dc header 1024 2.991122
36430f041d87935dcb34adde2e7d625d .text 78234112 6.471421
ee7e02e8e2958ff79f25c8fd8b7d33e5 .rdata 15596032 6.376243
65c59271f5c2bab26a7d0838e9f04bcf .data 262144 3.484705
00406f1d9355757d80cbf48242fdf344 .pdata 2768896 6.805097
6a6a225bfe091e65d3f82654179fbc50 .00cfg 512 0.195869
786f587a97128c401be15c90fe059b72 .rodata 6144 4.219562
9efa43af7b1faae15ffbd428d0485819 .tls 512 0.136464
60d3ea61d541c9be2e845d2787fb9574 CPADinfo 512 0.122276
bf619eac0cdf3f68d496ea9344137e8b prot 512 0.000000
fb5463e289f28642cc816a9010f32981 .rsrc 102912 4.766115
fb3216031225fdb1902888e247009d0c .reloc 709120 5.476445
Packers/Compilers/Cryptors
Microsoft Visual C++ 8.0 (DLL)
Relationships
78b56a1385… Contained_Within [Redacted]
Description

This file is a 64-bit Windows executable contained within the Windows MSI Installer “dorusio_win_v2.1.0.msi.” When executed, “Dorusio.exe” loads a legitimate looking cryptocurrency wallet application with no signs of malicious activity. Aside from the “Dorusio” logo and two new services, the wallet appears to be the same as the AppleJeus version 4 “Kupay wallet.”

This application appears to be a modification of the opensource cryptocurrency wallet Copay, which is distributed by Atlanta based company BitPay. According to the website “bitpay.com,” “BitPay builds powerful, enterprise-grade tools for crypto acceptance and spending”.

In addition to application appearance being similar, a DNS request for “bitpay.com” is always sent out immediately after a DNS request for “dorusio.com” and the company listed for “Dorusio” is Bitpay.

In addition, the GitHub “Commit Hash” listed in the “Dorusio” application “638b2b1” is to a branch of Copay found at hxxps[:]//github.com/flean/copay-1.

Screenshots