Malware Analysis Report

2025-04-13 11:57

Sample ID 240818-z9kyhayblr
Target Client-built.exe
SHA256 d00477c11f3c8ad73a0ea9c3c4b7e549754ed63b645a3a8f57de6dd2f89ec8d0
Tags
skids quasar spyware trojan discovery execution
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

d00477c11f3c8ad73a0ea9c3c4b7e549754ed63b645a3a8f57de6dd2f89ec8d0

Threat Level: Known bad

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

Malicious Activity Summary

skids quasar spyware trojan discovery execution

Quasar RAT

Quasar family

Quasar payload

Command and Scripting Interpreter: PowerShell

Executes dropped EXE

Checks computer location settings

Drops file in System32 directory

System Location Discovery: System Language Discovery

Unsigned PE

System Network Configuration Discovery: Internet Connection Discovery

Enumerates physical storage devices

Modifies Internet Explorer settings

Suspicious use of WriteProcessMemory

Modifies registry class

Uses Task Scheduler COM API

Suspicious use of AdjustPrivilegeToken

Suspicious use of FindShellTrayWindow

Suspicious use of SetWindowsHookEx

Suspicious use of SendNotifyMessage

Scheduled Task/Job: Scheduled Task

Runs ping.exe

Suspicious behavior: EnumeratesProcesses

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2024-08-18 21:25

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

2024-08-18 21:25

Reported

2024-08-18 21:27

Platform

win7-20240705-en

Max time kernel

128s

Max time network

153s

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\Windows\Windows Host Process.exe N/A

Drops file in System32 directory

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

Scheduled Task/Job: Scheduled Task

persistence execution
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

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\Windows\Windows Host Process.exe N/A

Suspicious use of FindShellTrayWindow

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

Suspicious use of SendNotifyMessage

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

Suspicious use of SetWindowsHookEx

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

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 Host Process" /sc ONLOGON /tr "C:\Windows\system32\Windows\Windows Host Process.exe" /rl HIGHEST /f

C:\Windows\system32\Windows\Windows Host Process.exe

"C:\Windows\system32\Windows\Windows Host Process.exe"

C:\Windows\system32\schtasks.exe

"schtasks" /create /tn "Windows Host Process" /sc ONLOGON /tr "C:\Windows\system32\Windows\Windows Host Process.exe" /rl HIGHEST /f

Network

Country Destination Domain Proto
US 147.185.221.22:6712 tcp
US 147.185.221.22:6712 tcp
US 147.185.221.22:6712 tcp
US 147.185.221.22:6712 tcp

Files

memory/2104-0-0x000007FEF6243000-0x000007FEF6244000-memory.dmp

memory/2104-1-0x0000000000A00000-0x0000000000D58000-memory.dmp

memory/2104-2-0x000007FEF6240000-0x000007FEF6C2C000-memory.dmp

C:\Windows\system32\Windows\Windows Host Process.exe

MD5 9eb8732b560208f0380c386771aba096
SHA1 d2ae1ff6755e79f97485aea27912ed7710378b08
SHA256 d00477c11f3c8ad73a0ea9c3c4b7e549754ed63b645a3a8f57de6dd2f89ec8d0
SHA512 686b1968a19d6f81562df6efd659060ecc7d2eceb7b053d530e8bcba030db6e7b55cb7c6364d6dddc7ea9a46b5004cae3a78db5b432ed279ce2fa854fa400b8a

memory/2680-10-0x000007FEF6240000-0x000007FEF6C2C000-memory.dmp

memory/2680-9-0x0000000000B60000-0x0000000000EB8000-memory.dmp

memory/2680-11-0x000007FEF6240000-0x000007FEF6C2C000-memory.dmp

memory/2104-8-0x000007FEF6240000-0x000007FEF6C2C000-memory.dmp

memory/2680-12-0x000007FEF6240000-0x000007FEF6C2C000-memory.dmp

Analysis: behavioral2

Detonation Overview

Submitted

2024-08-18 21:25

Reported

2024-08-18 21:35

Platform

win10v2004-20240802-en

Max time kernel

435s

Max time network

436s

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

Command and Scripting Interpreter: PowerShell

execution
Description Indicator Process Target
N/A N/A C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe N/A

Checks computer location settings

Description Indicator Process Target
Key value queried \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000\Control Panel\International\Geo\Nation C:\Windows\system32\Windows\Windows Host Process.exe N/A

Executes dropped EXE

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

Drops file in System32 directory

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

Enumerates physical storage devices

System Location Discovery: System Language Discovery

discovery
Description Indicator Process Target
Key opened \REGISTRY\MACHINE\SYSTEM\ControlSet001\Control\NLS\Language C:\Windows\SysWOW64\DllHost.exe N/A

System Network Configuration Discovery: Internet Connection Discovery

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

Modifies Internet Explorer settings

adware spyware
Description Indicator Process Target
Key created \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000\Software\Microsoft\Internet Explorer\Toolbar C:\Windows\explorer.exe N/A
Set value (int) \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000\SOFTWARE\Microsoft\Internet Explorer\Toolbar\Locked = "1" C:\Windows\explorer.exe N/A

Modifies registry class

Description Indicator Process Target
Key created \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000_Classes\Local Settings\Software\Microsoft\Windows\Shell C:\Windows\explorer.exe N/A
Key created \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000_Classes\Local Settings\Software\Microsoft\Windows\Shell\BagMRU C:\Windows\explorer.exe N/A
Set value (data) \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000_Classes\Local Settings\Software\Microsoft\Windows\Shell\BagMRU\NodeSlots C:\Windows\explorer.exe N/A
Set value (data) \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000_Classes\Local Settings\Software\Microsoft\Windows\Shell\BagMRU\MRUListEx = ffffffff C:\Windows\explorer.exe N/A
Key created \REGISTRY\USER\S-1-5-21-2392887640-1187051047-2909758433-1000_Classes\Local Settings C:\Windows\explorer.exe N/A

Runs ping.exe

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

Scheduled Task/Job: Scheduled Task

persistence execution
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

Suspicious behavior: EnumeratesProcesses

Description Indicator Process Target
N/A N/A C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe N/A
N/A N/A C:\Windows\System32\WindowsPowerShell\v1.0\powershell.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\Windows\Windows Host Process.exe N/A
Token: SeDebugPrivilege N/A C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe N/A

Suspicious use of SetWindowsHookEx

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

Suspicious use of WriteProcessMemory

Description Indicator Process Target
PID 5080 wrote to memory of 1368 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\SYSTEM32\schtasks.exe
PID 5080 wrote to memory of 1368 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\SYSTEM32\schtasks.exe
PID 5080 wrote to memory of 3896 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\Windows\Windows Host Process.exe
PID 5080 wrote to memory of 3896 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\Windows\Windows Host Process.exe
PID 3896 wrote to memory of 4968 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3896 wrote to memory of 4968 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3896 wrote to memory of 1912 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
PID 3896 wrote to memory of 1912 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
PID 3896 wrote to memory of 1488 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3896 wrote to memory of 1488 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\SYSTEM32\schtasks.exe
PID 3896 wrote to memory of 4604 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\system32\cmd.exe
PID 3896 wrote to memory of 4604 N/A C:\Windows\system32\Windows\Windows Host Process.exe C:\Windows\system32\cmd.exe
PID 4604 wrote to memory of 1520 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\chcp.com
PID 4604 wrote to memory of 1520 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\chcp.com
PID 4604 wrote to memory of 1360 N/A C:\Windows\system32\cmd.exe C:\Windows\system32\PING.EXE
PID 4604 wrote to memory of 1360 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 Host Process" /sc ONLOGON /tr "C:\Windows\system32\Windows\Windows Host Process.exe" /rl HIGHEST /f

C:\Windows\system32\Windows\Windows Host Process.exe

"C:\Windows\system32\Windows\Windows Host Process.exe"

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /create /tn "Windows Host Process" /sc ONLOGON /tr "C:\Windows\system32\Windows\Windows Host Process.exe" /rl HIGHEST /f

C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe

"powershell.exe" -Command "Add-MpPreference -ExclusionPath 'C:\'"

C:\Windows\SysWOW64\DllHost.exe

C:\Windows\SysWOW64\DllHost.exe /Processid:{06622D85-6856-4460-8DE1-A81921B41C4B}

C:\Windows\explorer.exe

C:\Windows\explorer.exe /factory,{5BD95610-9434-43C2-886C-57852CC8A120} -Embedding

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /delete /tn "Windows Host Process" /f

C:\Windows\system32\cmd.exe

C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\uCTdtSDvidJt.bat" "

C:\Windows\system32\chcp.com

chcp 65001

C:\Windows\system32\PING.EXE

ping -n 10 localhost

Network

Country Destination Domain Proto
US 8.8.8.8:53 241.150.49.20.in-addr.arpa udp
US 147.185.221.22:6712 tcp
US 8.8.8.8:53 73.31.126.40.in-addr.arpa udp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
US 8.8.8.8:53 22.221.185.147.in-addr.arpa udp
US 8.8.8.8:53 43.58.199.20.in-addr.arpa udp
US 8.8.8.8:53 209.205.72.20.in-addr.arpa udp
US 147.185.221.22:6712 tcp
US 8.8.8.8:53 ipwho.is udp
DE 195.201.57.90:443 ipwho.is tcp
US 8.8.8.8:53 240.143.123.92.in-addr.arpa udp
US 8.8.8.8:53 90.57.201.195.in-addr.arpa udp
US 8.8.8.8:53 26.165.165.52.in-addr.arpa udp
US 147.185.221.22:6712 tcp
US 8.8.8.8:53 15.164.165.52.in-addr.arpa udp
US 8.8.8.8:53 98.58.20.217.in-addr.arpa udp
US 8.8.8.8:53 tse1.mm.bing.net udp
US 150.171.28.10:443 tse1.mm.bing.net tcp
US 150.171.28.10:443 tse1.mm.bing.net tcp
US 150.171.28.10:443 tse1.mm.bing.net tcp
US 150.171.28.10:443 tse1.mm.bing.net tcp
US 150.171.28.10:443 tse1.mm.bing.net tcp
US 8.8.8.8:53 26.35.223.20.in-addr.arpa udp
US 8.8.8.8:53 10.28.171.150.in-addr.arpa udp
US 147.185.221.22:6712 tcp
US 8.8.8.8:53 92.16.208.104.in-addr.arpa udp
US 147.185.221.22:6712 tcp
US 147.185.221.22:6712 tcp
US 147.185.221.22:6712 tcp

Files

memory/5080-0-0x00007FFD1F223000-0x00007FFD1F225000-memory.dmp

memory/5080-1-0x0000000000790000-0x0000000000AE8000-memory.dmp

memory/5080-2-0x00007FFD1F220000-0x00007FFD1FCE1000-memory.dmp

C:\Windows\System32\Windows\Windows Host Process.exe

MD5 9eb8732b560208f0380c386771aba096
SHA1 d2ae1ff6755e79f97485aea27912ed7710378b08
SHA256 d00477c11f3c8ad73a0ea9c3c4b7e549754ed63b645a3a8f57de6dd2f89ec8d0
SHA512 686b1968a19d6f81562df6efd659060ecc7d2eceb7b053d530e8bcba030db6e7b55cb7c6364d6dddc7ea9a46b5004cae3a78db5b432ed279ce2fa854fa400b8a

memory/5080-9-0x00007FFD1F220000-0x00007FFD1FCE1000-memory.dmp

memory/3896-10-0x00007FFD1F220000-0x00007FFD1FCE1000-memory.dmp

memory/3896-11-0x00007FFD1F220000-0x00007FFD1FCE1000-memory.dmp

memory/3896-12-0x000000001B8F0000-0x000000001B940000-memory.dmp

memory/3896-13-0x000000001C100000-0x000000001C1B2000-memory.dmp

memory/3896-14-0x00007FFD1F220000-0x00007FFD1FCE1000-memory.dmp

memory/3896-17-0x000000001C090000-0x000000001C0A2000-memory.dmp

memory/3896-18-0x000000001CE00000-0x000000001CE3C000-memory.dmp

C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_v5rvylxm.2rd.ps1

MD5 d17fe0a3f47be24a6453e9ef58c94641
SHA1 6ab83620379fc69f80c0242105ddffd7d98d5d9d
SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
SHA512 5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

memory/1912-24-0x0000028E346F0000-0x0000028E34712000-memory.dmp

memory/3896-31-0x000000001D670000-0x000000001DB98000-memory.dmp

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

MD5 965c829039f3d549a5905a168ee34311
SHA1 dc572eeb4e27bb6892ed39ae05506bf76c9c2a38
SHA256 b17acacbd92259fbab080f8d284f6b971493561f8b7243972309289949a9d522
SHA512 6045c9a65cdaa78222dc3eab4320522fe868077d635c8aecf8effcdadd2219747cdfad67175ecc061e88b94465664b1401091a5fa65cba7f3006f27b39b37fae

memory/3896-41-0x00007FFD1F220000-0x00007FFD1FCE1000-memory.dmp