Malware Analysis Report (AR21-048D)

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 Lazarus Group 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)

55eacc25e9eaba5d3f04b6cbcac2e16879b83d967596d645e5ec4b8f42656ef9 (Kupay.dmg)

6b945159b4c816ec5e212ba125eb01938234205d8d3e57fca46de7c064c628f8 (Kupay.msi)

91eaf215be336eae983d069de16630cc3580e222c427f785e0da312d0692d0fd (kupayupdate_stage2)

a0c461c94ba9f1573c7253666d218b3343d24bfa5d8ef270ee9bc74b7856e492 (kupay)

fc1aafd2ed190fa523e60c3d22b6f7ca049d97fc41c9a2fe987576d6b5e81d6d (KupayUpgrade.exe)

Domains (2)

kupaywallet.com

levelframeblog.com

6b945159b4c816ec5e212ba125eb01938234205d8d3e57fca46de7c064c628f8

Tags

dropper

Details

Antivirus

No matches found.

YARA Rules

No matches found.

ssdeep Matches

No matches found.

Relationships

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

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

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

1b60a6d35c872102f535ae6a3d7669fb7d55c43dc7e73354423fdcca01a955d6

Tags

trojan

Details

Antivirus

No matches found.

YARA Rules

No matches found.

ssdeep Matches

PE Metadata

PE Sections

Packers/Compilers/Cryptors

Relationships

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

fc1aafd2ed190fa523e60c3d22b6f7ca049d97fc41c9a2fe987576d6b5e81d6d

Tags

trojan

Details

Antivirus

YARA Rules

No matches found.

ssdeep Matches

PE Metadata

PE Sections

Packers/Compilers/Cryptors

Relationships

Description

This file is a 64-bit Windows executable contained within the Windows MSI Installer "Kupay.msi." When executed, "KupayUpgrade.exe" first installs itself as a service, which will automatically start when any user logs on. The service is installed with a description stating “Automatic Kupay Upgrade."

On startup, "KupayUpgrade.exe" allocates memory in order to later write a file. After allocating the memory and storing the hard-coded string “Latest” in a variable, the program attempts to open a network connection. The connection is named “Kupay Wallet 9.0.1 (Check Update Windows)”, likely to avoid suspicion from a user.

Similarly to previous AppleJeus variants, "KupayUpgrade.exe "collects some basic information from the system as well as a timestamp, and places them in hard coded format strings. Specifically, the timestamp is placed into a format string “ver=%d&timestamp=%lu” where ver is set as the 90001, possibly referring to the Kupay Wallet version previously mentioned (Figure 7).

This basic information and hard-coded strings are sent via a POST to the C2 kupaywallet.com/kupay_update.php. If the POST is successful (i.e. returns an HTTP response status code of 200) but fails any of multiple different checks, "KupayUpgrade.exe" will sleep for two minutes and then regenerate the timestamp and contact the C2 again.

After receiving the payload from the C2, the program writes the payload to memory and executes the payload.

The payload for the Windows malware could not be downloaded, as the C2 server "kupaywallet.com/kupay_update.php" was no longer accessible. In addition, the sample was not identified in open source reporting for this sample.

Screenshots