Delta Group

Delta, Cyber Struggle bünyesinde multidisipliner araştırmalar yürüten resmi topluluktur. Başta siber güvenlik olmak üzere, terör, 4. nesil savaşlar, hibrit savaşlar, profilleme, psikolojik harekat, uluslararası ilişkiler ve kriminoloji gibi çeşitli alanların, siber dünya uygulamaları üzerine araştırma geliştirme faaliyetlerinde bulunur.

Son Yazılar

İletişim

delta@cyberstruggle.org

Summary

This is the analysis report of a malicious Word document used in a Phishing campaign targeting financial organizations and cryptocurrency exchanges. This dropper file is exploiting a vulnerability in Adobe Flash in order to download & execute the second stage malware. Components and general outline is shown in image below.

SECURITY ANALYSIS OF THE MOST POPULAR CRYPTOCURRENCY EXCHANGES.DOCX

This is the initial document which is delivered over a Phishing E-mail. Its main task is to drop the 2nd stage payload. It contains a second document file with the name of “activeX1.bin”. Contents are shown in the screenshot below.

Contents of File

Content of Docx File

ACTIVEX1.BIN

This file is the type of “Word Processing Document”. We discovered that there is a Flash object embedded in this document. We have successfully extracted and analysed the aforementioned SWF file as seen below.

Flash Object Found

FLASH EXPLOIT CVE-2018-4878

This file exploits an use-after free vulnerability in Adobe Flash (CVE-2018-4878 *) in order to gain arbitrary code execution. If successful it connects to domain “falcancoin.io” to download the 2nd stage payload, and executes it. Basic code obfuscation techniques are present and the shellcode is contained under the “binaryData” section. We have managed to extract and analyse the shellcode as seen below.

Shellcode Contained in binaryData Section

Shellcode Strings

Initial procedure of this shellcode is to search through the memory for a constant value (hexadecimal: AABBCCDD). We believe that this constant value is a seperator for different sections of the shellcode.

Searching Procedure

While this being similar to an exploitation technique calledEgg Huntingwe consider it to be a characteristic of this shellcode. So below we have created a YARA signature to detect this payload.

$find_signature = {8B 4D 04 31 C0 81 3C 08 ?? ?? ?? ?? 74 0A 40 3D 00 01 00 00 72 EF 5D C3}

Section A of Shellcode

Section B of Shellcode

PACKAGE32.ZIP

This is the second stage payload dropped by the aforementioned shellcode. It’s identified that this is indeed the BankShot implant of the threat actor group dubbed as HiddenCobra or Lazarus. Common anti analysis measures are present. This implant also carry abilities like persistency and command execution, and communicating via a custom protocol built on HTTP. Screenshots regarding to some of our findings are below.

Filenames C2 domains and Windows Commands

Common anti analysis trick leveraging timing attack

Initial communication with C2

Implant querying host's User Agent string in order to use it in communications therefore its traffic will look less suspicious

You can read the full analysis report written by McAfee on this implant here: https://securingtomorrow.mcafee.com/mcafee-labs/hidden-cobra-targets-turkish-financial-sector-new-bankshot-implant/

INDICATORS OF COMPROMISE

Type Signature Description
Domain falcancoin.io Host of Hidden Cobre
Domain 530hr.com C2 Domain
Domain 028xmz.com Backup C2
Domain 168wangpi.com Backup C2
MD5 b99e5cf00d084aadb938b8db721c026a activeX1.bin
MD5 9e819a142e1287a9fd72b317b575ad17 CVE-2018-4878.swf
MD5 0e3e891d5235a7880bd4c7bb04430185 Exploit Payload
MD5 12c786c490366727cf7279fc141921d8 package32.zip
MD5 1b3ebec6ce48241c6715e19713a95f1b Security analysis of the most popular cryptocurrency exchanges.docx
YARA $find_signature = {8B 4D 04 31 C0 81 3C 08 ?? ?? ?? ?? 74 0A 40 3D 00 01 00 00 72 EF 5D C3} Signature searching routine of exploit payload

Delta Group

Delta, Cyber Struggle bünyesinde multidisipliner araştırmalar yürüten resmi topluluktur. Başta siber güvenlik olmak üzere, terör, 4. nesil savaşlar, hibrit savaşlar, profilleme, psikolojik harekat, uluslararası ilişkiler ve kriminoloji gibi çeşitli alanların, siber dünya uygulamaları üzerine araştırma geliştirme faaliyetlerinde bulunur.

Son Yazılar

İletişim

delta@cyberstruggle.org

Summary

This is the analysis report of a malicious Word document used in a Phishing campaign targeting financial organizations and cryptocurrency exchanges. This dropper file is exploiting a vulnerability in Adobe Flash in order to download & execute the second stage malware. Components and general outline is shown in image below.

SECURITY ANALYSIS OF THE MOST POPULAR CRYPTOCURRENCY EXCHANGES.DOCX

This is the initial document which is delivered over a Phishing E-mail. Its main task is to drop the 2nd stage payload. It contains a second document file with the name of “activeX1.bin”. Contents are shown in the screenshot below.

Contents of File

Content of Docx File

ACTIVEX1.BIN

This file is the type of “Word Processing Document”. We discovered that there is a Flash object embedded in this document. We have successfully extracted and analysed the aforementioned SWF file as seen below.

Flash Object Found

FLASH EXPLOIT CVE-2018-4878

This file exploits an use-after free vulnerability in Adobe Flash (CVE-2018-4878 *) in order to gain arbitrary code execution. If successful it connects to domain “falcancoin.io” to download the 2nd stage payload, and executes it. Basic code obfuscation techniques are present and the shellcode is contained under the “binaryData” section. We have managed to extract and analyse the shellcode as seen below.

Shellcode Contained in binaryData Section

Shellcode Strings

Initial procedure of this shellcode is to search through the memory for a constant value (hexadecimal: AABBCCDD). We believe that this constant value is a seperator for different sections of the shellcode.

Searching Procedure

While this being similar to an exploitation technique calledEgg Huntingwe consider it to be a characteristic of this shellcode. So below we have created a YARA signature to detect this payload.

$find_signature = {8B 4D 04 31 C0 81 3C 08 ?? ?? ?? ?? 74 0A 40 3D 00 01 00 00 72 EF 5D C3}

Section A of Shellcode

Section B of Shellcode

PACKAGE32.ZIP

This is the second stage payload dropped by the aforementioned shellcode. It’s identified that this is indeed the BankShot implant of the threat actor group dubbed as HiddenCobra or Lazarus. Common anti analysis measures are present. This implant also carry abilities like persistency and command execution, and communicating via a custom protocol built on HTTP. Screenshots regarding to some of our findings are below.

Filenames C2 domains and Windows Commands

Common anti analysis trick leveraging timing attack

Initial communication with C2

Implant querying host's User Agent string in order to use it in communications therefore its traffic will look less suspicious

You can read the full analysis report written by McAfee on this implant here: https://securingtomorrow.mcafee.com/mcafee-labs/hidden-cobra-targets-turkish-financial-sector-new-bankshot-implant/

INDICATORS OF COMPROMISE

Type Signature Description
Domain falcancoin.io Host of Hidden Cobre
Domain 530hr.com C2 Domain
Domain 028xmz.com Backup C2
Domain 168wangpi.com Backup C2
MD5 b99e5cf00d084aadb938b8db721c026a activeX1.bin
MD5 9e819a142e1287a9fd72b317b575ad17 CVE-2018-4878.swf
MD5 0e3e891d5235a7880bd4c7bb04430185 Exploit Payload
MD5 12c786c490366727cf7279fc141921d8 package32.zip
MD5 1b3ebec6ce48241c6715e19713a95f1b Security analysis of the most popular cryptocurrency exchanges.docx
YARA $find_signature = {8B 4D 04 31 C0 81 3C 08 ?? ?? ?? ?? 74 0A 40 3D 00 01 00 00 72 EF 5D C3} Signature searching routine of exploit payload