Malware Analysis Report

2024-10-19 08:41

Sample ID 240419-m9cwnsab73
Target Client-built.exe
SHA256 a5473ea4c4ef75c217e0d252d1c7d235b781a75810b7e731a97ed78b45646840
Tags
office04 quasar spyware trojan
score
10/10

Table of Contents

Analysis Overview

MITRE ATT&CK

Enterprise Matrix V15

Analysis: static1

Detonation Overview

Signatures

Analysis: behavioral1

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis: behavioral2

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
10/10

SHA256

a5473ea4c4ef75c217e0d252d1c7d235b781a75810b7e731a97ed78b45646840

Threat Level: Known bad

The file Client-built.exe was found to be: Known bad.

Malicious Activity Summary

office04 quasar spyware trojan

Quasar payload

Quasar RAT

Quasar family

Executes dropped EXE

Drops file in System32 directory

Enumerates physical storage devices

Unsigned PE

Suspicious use of SetWindowsHookEx

Suspicious use of FindShellTrayWindow

Suspicious use of SendNotifyMessage

Uses Task Scheduler COM API

Creates scheduled task(s)

Runs ping.exe

Suspicious use of AdjustPrivilegeToken

Suspicious use of WriteProcessMemory

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2024-04-19 11:09

Signatures

Quasar family

quasar

Quasar payload

Description Indicator Process Target
N/A N/A N/A N/A

Unsigned PE

Description Indicator Process Target
N/A N/A N/A N/A

Analysis: behavioral1

Detonation Overview

Submitted

2024-04-19 11:09

Reported

2024-04-19 11:10

Platform

win7-20240221-en

Max time kernel

15s

Max time network

19s

Command Line

"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"

Signatures

Quasar RAT

trojan spyware quasar

Quasar payload

Description Indicator Process Target
N/A N/A N/A N/A
N/A N/A N/A N/A
N/A N/A N/A N/A

Executes dropped EXE

Description Indicator Process Target
N/A N/A C:\Windows\system32\SubDir\updale.exe N/A

Drops file in System32 directory

Description Indicator Process Target
File created C:\Windows\system32\SubDir\updale.exe C:\Users\Admin\AppData\Local\Temp\Client-built.exe N/A
File opened for modification C:\Windows\system32\SubDir\updale.exe C:\Users\Admin\AppData\Local\Temp\Client-built.exe N/A
File opened for modification C:\Windows\system32\SubDir C:\Users\Admin\AppData\Local\Temp\Client-built.exe N/A
File opened for modification C:\Windows\system32\SubDir\updale.exe C:\Windows\system32\SubDir\updale.exe N/A
File opened for modification C:\Windows\system32\SubDir C:\Windows\system32\SubDir\updale.exe N/A

Enumerates physical storage devices

Creates scheduled task(s)

persistence
Description Indicator Process Target
N/A N/A C:\Windows\system32\schtasks.exe N/A
N/A N/A C:\Windows\system32\schtasks.exe N/A

Runs ping.exe

Description Indicator Process Target
N/A N/A C:\Windows\system32\PING.EXE N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe N/A
Token: SeDebugPrivilege N/A C:\Windows\system32\SubDir\updale.exe N/A

Suspicious use of FindShellTrayWindow

Description Indicator Process Target
N/A N/A C:\Windows\system32\SubDir\updale.exe N/A

Suspicious use of SendNotifyMessage

Description Indicator Process Target
N/A N/A C:\Windows\system32\SubDir\updale.exe N/A

Suspicious use of SetWindowsHookEx

Description Indicator Process Target
N/A N/A C:\Windows\system32\SubDir\updale.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 2240 wrote to memory of 1532 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\schtasks.exe
PID 2240 wrote to memory of 1532 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\schtasks.exe
PID 2240 wrote to memory of 1532 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\schtasks.exe
PID 2240 wrote to memory of 2540 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\SubDir\updale.exe
PID 2240 wrote to memory of 2540 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\SubDir\updale.exe
PID 2240 wrote to memory of 2540 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\SubDir\updale.exe
PID 2540 wrote to memory of 2612 N/A C:\Windows\system32\SubDir\updale.exe C:\Windows\system32\schtasks.exe
PID 2540 wrote to memory of 2612 N/A C:\Windows\system32\SubDir\updale.exe C:\Windows\system32\schtasks.exe
PID 2540 wrote to memory of 2612 N/A C:\Windows\system32\SubDir\updale.exe C:\Windows\system32\schtasks.exe
PID 2540 wrote to memory of 2420 N/A C:\Windows\system32\SubDir\updale.exe C:\Windows\system32\cmd.exe
PID 2540 wrote to memory of 2420 N/A C:\Windows\system32\SubDir\updale.exe C:\Windows\system32\cmd.exe
PID 2540 wrote to memory of 2420 N/A C:\Windows\system32\SubDir\updale.exe C:\Windows\system32\cmd.exe
PID 2420 wrote to memory of 2696 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\chcp.com
PID 2420 wrote to memory of 2696 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\chcp.com
PID 2420 wrote to memory of 2696 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\chcp.com
PID 2420 wrote to memory of 2400 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\PING.EXE
PID 2420 wrote to memory of 2400 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\PING.EXE
PID 2420 wrote to memory of 2400 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\PING.EXE

Uses Task Scheduler COM API

persistence

Processes

C:\Users\Admin\AppData\Local\Temp\Client-built.exe

"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"

C:\Windows\system32\schtasks.exe

"schtasks" /create /tn "windows av startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\updale.exe" /rl HIGHEST /f

C:\Windows\system32\SubDir\updale.exe

"C:\Windows\system32\SubDir\updale.exe"

C:\Windows\system32\schtasks.exe

"schtasks" /create /tn "windows av startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\updale.exe" /rl HIGHEST /f

C:\Windows\system32\cmd.exe

cmd /c ""C:\Users\Admin\AppData\Local\Temp\pmknLoE48RGB.bat" "

C:\Windows\system32\chcp.com

chcp 65001

C:\Windows\system32\PING.EXE

ping -n 10 localhost

Network

Country Destination Domain Proto
US 8.8.8.8:53 funlink.ddns.net udp

Files

memory/2240-0-0x0000000000EA0000-0x00000000011C4000-memory.dmp

memory/2240-1-0x000007FEF5700000-0x000007FEF60EC000-memory.dmp

memory/2240-2-0x000000001AD40000-0x000000001ADC0000-memory.dmp

C:\Windows\System32\SubDir\updale.exe

MD5 2c1fba8d6624adf6c582fb2d5fb43b28
SHA1 bd45ee984e9476d604824f83c6cf6111a9db2467
SHA256 a5473ea4c4ef75c217e0d252d1c7d235b781a75810b7e731a97ed78b45646840
SHA512 cc85b5f1c2765c49f34c236634dcbfdfd6cc62e0b954b74c12b0d89dc29044dff88a9840e5c02a39e140564283074c78359dd70dfc7f426daefb75f195f14e19

memory/2240-8-0x000007FEF5700000-0x000007FEF60EC000-memory.dmp

memory/2540-10-0x000007FEF5700000-0x000007FEF60EC000-memory.dmp

memory/2540-9-0x0000000000E00000-0x0000000001124000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\pmknLoE48RGB.bat

MD5 9cce0dca1ef1148360b651f825223599
SHA1 014b0417c7daa19d4389080d54fe174340a12784
SHA256 0a6ad1828f76c970269eef4db6b9d818986290c8bf8e1a551ea4f0f80bb2b725
SHA512 079b6727d575cb411489b15de50fbf551aa948794b517e4d8d6aff95ae57dd54bfefb065ad7a6bfa27a64b7c5fd53531bb57a5a0648afd10d014017f7f387b0d

memory/2540-20-0x000007FEF5700000-0x000007FEF60EC000-memory.dmp

Analysis: behavioral2

Detonation Overview

Submitted

2024-04-19 11:09

Reported

2024-04-19 11:12

Platform

win10v2004-20240226-en

Max time kernel

135s

Max time network

162s

Command Line

"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"

Signatures

Quasar RAT

trojan spyware quasar

Quasar payload

Description Indicator Process Target
N/A N/A N/A N/A

Drops file in System32 directory

Description Indicator Process Target
File created C:\Windows\system32\SubDir\updale.exe C:\Users\Admin\AppData\Local\Temp\Client-built.exe N/A
File opened for modification C:\Windows\system32\SubDir\updale.exe C:\Users\Admin\AppData\Local\Temp\Client-built.exe N/A

Creates scheduled task(s)

persistence
Description Indicator Process Target
N/A N/A C:\Windows\SYSTEM32\schtasks.exe N/A

Suspicious use of AdjustPrivilegeToken

Description Indicator Process Target
Token: SeDebugPrivilege N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe N/A

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 1504 wrote to memory of 1436 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\SYSTEM32\schtasks.exe
PID 1504 wrote to memory of 1436 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\SYSTEM32\schtasks.exe

Uses Task Scheduler COM API

persistence

Processes

C:\Users\Admin\AppData\Local\Temp\Client-built.exe

"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"

C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe

"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --type=utility --utility-sub-type=asset_store.mojom.AssetStoreService --lang=en-US --service-sandbox-type=asset_store_service --no-appcompat-clear --mojo-platform-channel-handle=4144 --field-trial-handle=2276,i,11674642242468042059,14711253743544118298,262144 --variations-seed-version /prefetch:8

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /create /tn "windows av startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\updale.exe" /rl HIGHEST /f

Network

Country Destination Domain Proto
US 8.8.8.8:53 133.211.185.52.in-addr.arpa udp
US 8.8.8.8:53 82.90.14.23.in-addr.arpa udp
US 8.8.8.8:53 103.169.127.40.in-addr.arpa udp
US 8.8.8.8:53 198.187.3.20.in-addr.arpa udp
US 8.8.8.8:53 24.139.73.23.in-addr.arpa udp
US 8.8.8.8:53 71.159.190.20.in-addr.arpa udp
US 8.8.8.8:53 19.229.111.52.in-addr.arpa udp
US 8.8.8.8:53 91.90.14.23.in-addr.arpa udp
US 8.8.8.8:53 183.142.211.20.in-addr.arpa udp
US 8.8.8.8:53 232.168.11.51.in-addr.arpa udp
US 8.8.8.8:53 171.117.168.52.in-addr.arpa udp

Files

memory/1504-0-0x00000000005D0000-0x00000000008F4000-memory.dmp

memory/1504-1-0x00007FFA05EA0000-0x00007FFA06961000-memory.dmp

memory/1504-2-0x000000001B600000-0x000000001B610000-memory.dmp

memory/1504-3-0x00007FFA05EA0000-0x00007FFA06961000-memory.dmp

memory/1504-4-0x000000001B600000-0x000000001B610000-memory.dmp