Malware Analysis – AppleJeus: Kupay Wallet

Fortify Security Team
Feb 18, 2021

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—Kupay Wallet—and associated IOCs used by the North Korean government in AppleJeus operations.

Kupay Wallet, discovered in March 2020, is a legitimate-looking cryptocurrency trading software that is marketed and distributed by a company and website—Kupay Service and kupaywallet[.]com, respectively—that appear legitimate. Some information has been redacted from this report to preserve victim anonymity.

For a downloadable copy of IOCs, see: MAR-10322463-4.v1.stix.

Submitted Files (7)

0bc7517aa2f0c1820ced399bfd66b993f10ad77e8d72727b0f3dc1ca35cad7ba (kupay_upgrade)

1b60a6d35c872102f535ae6a3d7669fb7d55c43dc7e73354423fdcca01a955d6 (Kupay.exe)

[Redacted] (Kupay.dmg)

[Redacted] (Kupay.msi)

91eaf215be336eae983d069de16630cc3580e222c427f785e0da312d0692d0fd (kupayupdate_stage2)

a0c461c94ba9f1573c7253666d218b3343d24bfa5d8ef270ee9bc74b7856e492 (kupay)

fc1aafd2ed190fa523e60c3d22b6f7ca049d97fc41c9a2fe987576d6b5e81d6d (KupayUpgrade.exe)

Domains (2)

kupaywallet.com

levelframeblog.com

Findings

[Redacted]

Tags

dropper

Details
Name Kupay.msi
Size [Redacted] 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: Kupay, Author: Kupay Service, 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 Kupay., 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] Contains 1b60a6d35c872102f535ae6a3d7669fb7d55c43dc7e73354423fdcca01a955d6
[Redacted] Contains fc1aafd2ed190fa523e60c3d22b6f7ca049d97fc41c9a2fe987576d6b5e81d6d
[Redacted] Downloaded_By kupaywallet.com
Description

This Windows program from the Kupay Service site is a Windows MSI Installer with the file name Kupay[GUID].msi. The installer was hosted at hxxps[:]kupaywallet.com/product/[GUID]. The [GUID] is a unique file that is crated for a specific victim and is being withheld to preserve the identity of the intended recipient.

The installer looks legitimate and will install the “Kupay.exe” (1b60a6d35c872102f535ae6a3d7669fb7d55c43dc7e73354423fdcca01a955d6) file in the “C:\Program Files (x86)\Kupay” folder. It also installs “KupayUpgrade.exe” (fc1aafd2ed190fa523e60c3d22b6f7ca049d97fc41c9a2fe987576d6b5e81d6d) in the “C:\Users\<username>\AppData\Roaming\KupaySupport” folder. Immediately after installation, the installer launches the “KupayUpgrade.exe” binary.

Screenshots

Figure 1 - Screenshot of "Kupay.msi" installation.

Figure 1 – Screenshot of “Kupay.msi” installation.

kupaywallet.com

Tags

command-and-control

URLs
  • kupaywallet.com/kupay_update.php
  • kupaywallet.com/product/
Whois

Whois for kupaywallet.com had the following information:
Registrar: NAMECHEAP INC
Creation Date: 2020-02-21
Registrar Registration Expiration Date: 2021-02-21

Relationships
kupaywallet.com Downloaded [Redacted]
kupaywallet.com Downloaded [Redacted]
kupaywallet.com Connected_From 0bc7517aa2f0c1820ced399bfd66b993f10ad77e8d72727b0f3dc1ca35cad7ba
Description

The domain kupaywallet.com had a legitimately signed Sectigo Secure Sockets Layer (SSL) certificate, which was “Domain Control Validated” just as all previous AppleJeus domain certificates. Investigation revealed the point of contact listed for verification was admin[@]kupaywallet.com. No other contact information was available as the administrative or technical contact for the kupaywallet.com domain.

The domain is registered with NameCheap at the IP address 104.200.67.96 with ASN 8100.

In addition to the site kupaywallet.com, a Twitter account @kupayservice is associated with the company. This account tweets out general cryptocurrency articles and information and replies to various related tweets. The first tweet was on May 23, 2019, while the last was on July 11, 2019. Twitter lists the joined date for @kupayservice to be October 2018.

Screenshots

Figure 2 - Screenshot of KupayService Twitter account.

Figure 2 – Screenshot of KupayService Twitter account.

1b60a6d35c872102f535ae6a3d7669fb7d55c43dc7e73354423fdcca01a955d6

Tags

trojan

Details
Name Kupay.exe
Size 97686016 bytes
Type PE32+ executable (GUI) x86-64, for MS Windows
MD5 668d696582f9c00029e2e8253470e9db
SHA1 e83ebe43da7bbfb9c95d34163383d1b3926e663f
SHA256 1b60a6d35c872102f535ae6a3d7669fb7d55c43dc7e73354423fdcca01a955d6
SHA512 0b370636ea2b7211d691a3bfcfc9017cb12df6874becb9b6334ca735bc325f59c50e99fc3b57c8db2d265e0c631651c7280109ffdbb3b48b7d3709d908228de6
ssdeep 1572864:MdJvugr82jf19dUM/1T8+1VJRukUhkmG:Mdhg6Pm
Entropy 6.674838
Antivirus

No matches found.

YARA Rules

No matches found.

ssdeep Matches
97 78b56a1385f2a92f3c9404f71731088646aac6c2c84cc19a449976272dab418f
PE Metadata
Compile Date 2019-12-16 00:00:00-05:00
Import Hash bb1d46df79ee2045d0bc2529cf6c7458
Company Name BitPay
File Description Kupay
Internal Name Kupay
Legal Copyright Copyright © 2020 BitPay
Product Name Kupay
Product Version 9.1.0.0
PE Sections
MD5 Name Raw Size Entropy
32b731864b0ff3d1c427c97d582e7897 header 1024 2.990247
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
85237257867935c227d2f2f39316b12a .rsrc 106496 4.912524
fb3216031225fdb1902888e247009d0c .reloc 709120 5.476445
Packers/Compilers/Cryptors
Microsoft Visual C++ 8.0 (DLL)
Relationships
1b60a6d35c… Contained_Within [Redacted]
Description

This file is a 64-bit Windows executable contained within the Windows MSI Installer “Kupay.msi.” When executed, “Kupay.exe” loads a legitimate looking cryptocurrency wallet application with no signs of malicious activity. This application appears to be a modification of the open source cryptocurrency wallet Copay, which is distributed by Atlanta based company BitPay. According to their 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 “kupaywallet.com” and the company listed in the version information for Kupay is Bitpay.

Lastly, the GitHub “Commit Hash” listed in the Dorusio application “638b2b1” is to a branch of Copay found at hxxps[:]//github.com/flean/copay-1 (Figure 5).

Screenshots