Malware Analysis Report

2025-01-18 04:11

Sample ID 241103-h11txsybnc
Target Client-built.exe
SHA256 597a26bc8399acff834bbce2ccbe7d5bab0e190e7f9163c2bce5feacc7f77ee9
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: behavioral3

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis: behavioral4

Detonation Overview

Command Line

Signatures

Processes

Network

Files

Analysis Overview

score
10/10

SHA256

597a26bc8399acff834bbce2ccbe7d5bab0e190e7f9163c2bce5feacc7f77ee9

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

Unsigned PE

Enumerates physical storage devices

Suspicious use of SendNotifyMessage

Suspicious use of FindShellTrayWindow

Scheduled Task/Job: Scheduled Task

Suspicious use of AdjustPrivilegeToken

Uses Task Scheduler COM API

Suspicious use of WriteProcessMemory

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2024-11-03 07:12

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

2024-11-03 07:12

Reported

2024-11-03 07:15

Platform

win10v2004-20241007-en

Max time kernel

137s

Max time network

146s

Command Line

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

Signatures

Quasar RAT

trojan spyware quasar

Quasar family

quasar

Quasar payload

Description Indicator Process Target
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:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Enumerates physical storage devices

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:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Suspicious use of FindShellTrayWindow

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Suspicious use of SendNotifyMessage

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\SubDir\Client.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 "Quasar Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f

C:\Users\Admin\AppData\Roaming\SubDir\Client.exe

"C:\Users\Admin\AppData\Roaming\SubDir\Client.exe"

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /create /tn "Quasar Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f

Network

Country Destination Domain Proto
US 8.8.8.8:53 196.249.167.52.in-addr.arpa udp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
US 8.8.8.8:53 68.32.126.40.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 88.156.103.20.in-addr.arpa udp
US 8.8.8.8:53 209.205.72.20.in-addr.arpa udp
US 8.8.8.8:53 58.55.71.13.in-addr.arpa udp
US 8.8.8.8:53 217.106.137.52.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 212.20.149.52.in-addr.arpa udp
US 8.8.8.8:53 198.187.3.20.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 88.210.23.2.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 48.229.111.52.in-addr.arpa udp
US 8.8.8.8:53 tse1.mm.bing.net udp
US 150.171.27.10:443 tse1.mm.bing.net tcp
US 150.171.27.10:443 tse1.mm.bing.net tcp
US 150.171.27.10:443 tse1.mm.bing.net tcp
US 150.171.27.10:443 tse1.mm.bing.net tcp
US 150.171.27.10:443 tse1.mm.bing.net tcp
N/A 192.168.0.18:4782 tcp
N/A 192.168.0.18:4782 tcp

Files

memory/1460-0-0x00007FFFAEA13000-0x00007FFFAEA15000-memory.dmp

memory/1460-1-0x00000000004B0000-0x00000000007D4000-memory.dmp

memory/1460-2-0x00007FFFAEA10000-0x00007FFFAF4D1000-memory.dmp

C:\Users\Admin\AppData\Roaming\SubDir\Client.exe

MD5 671df8e1c2f83f10f1cfb3f447299806
SHA1 9586ee12e49e5fbac96adfd5f3d59e4dfb8393f0
SHA256 597a26bc8399acff834bbce2ccbe7d5bab0e190e7f9163c2bce5feacc7f77ee9
SHA512 097a01e399d7527b0fc2bf952e7153d56b255897ef3f219cbd32938072d4ea66e62894d66f6b0ca80fbfda5c02738497d60c2ea415b0f900941a9c3121619690

memory/1460-9-0x00007FFFAEA10000-0x00007FFFAF4D1000-memory.dmp

memory/116-8-0x00007FFFAEA10000-0x00007FFFAF4D1000-memory.dmp

memory/116-10-0x00007FFFAEA10000-0x00007FFFAF4D1000-memory.dmp

memory/116-11-0x000000001D650000-0x000000001D6A0000-memory.dmp

memory/116-12-0x000000001D760000-0x000000001D812000-memory.dmp

memory/116-13-0x00007FFFAEA10000-0x00007FFFAF4D1000-memory.dmp

Analysis: behavioral2

Detonation Overview

Submitted

2024-11-03 07:12

Reported

2024-11-03 07:15

Platform

win10ltsc2021-20241023-en

Max time kernel

127s

Max time network

146s

Command Line

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

Signatures

Quasar RAT

trojan spyware quasar

Quasar family

quasar

Quasar payload

Description Indicator Process Target
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:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Enumerates physical storage devices

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:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Suspicious use of FindShellTrayWindow

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Suspicious use of SendNotifyMessage

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\SubDir\Client.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 "Quasar Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f

C:\Users\Admin\AppData\Roaming\SubDir\Client.exe

"C:\Users\Admin\AppData\Roaming\SubDir\Client.exe"

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /create /tn "Quasar Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f

Network

Country Destination Domain Proto
US 8.8.8.8:53 8.8.8.8.in-addr.arpa udp
US 8.8.8.8:53 58.55.71.13.in-addr.arpa udp
US 8.8.8.8:53 172.214.232.199.in-addr.arpa udp
US 8.8.8.8:53 68.32.126.40.in-addr.arpa udp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 217.106.137.52.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 53.210.109.20.in-addr.arpa udp
US 8.8.8.8:53 198.187.3.20.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 240.221.184.93.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
N/A 192.168.0.18:4782 tcp
N/A 192.168.0.18:4782 tcp

Files

memory/4460-0-0x00007FFE261B3000-0x00007FFE261B5000-memory.dmp

memory/4460-1-0x00000000009B0000-0x0000000000CD4000-memory.dmp

memory/4460-2-0x00007FFE261B0000-0x00007FFE26C72000-memory.dmp

C:\Users\Admin\AppData\Roaming\SubDir\Client.exe

MD5 671df8e1c2f83f10f1cfb3f447299806
SHA1 9586ee12e49e5fbac96adfd5f3d59e4dfb8393f0
SHA256 597a26bc8399acff834bbce2ccbe7d5bab0e190e7f9163c2bce5feacc7f77ee9
SHA512 097a01e399d7527b0fc2bf952e7153d56b255897ef3f219cbd32938072d4ea66e62894d66f6b0ca80fbfda5c02738497d60c2ea415b0f900941a9c3121619690

memory/4460-5-0x00007FFE261B0000-0x00007FFE26C72000-memory.dmp

memory/2532-6-0x00007FFE261B0000-0x00007FFE26C72000-memory.dmp

memory/2532-7-0x00007FFE261B0000-0x00007FFE26C72000-memory.dmp

memory/2532-8-0x000000001D710000-0x000000001D760000-memory.dmp

memory/2532-9-0x000000001D820000-0x000000001D8D2000-memory.dmp

memory/2532-10-0x00007FFE261B0000-0x00007FFE26C72000-memory.dmp

Analysis: behavioral3

Detonation Overview

Submitted

2024-11-03 07:12

Reported

2024-11-03 07:15

Platform

win11-20241007-en

Max time kernel

127s

Max time network

146s

Command Line

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

Signatures

Quasar RAT

trojan spyware quasar

Quasar family

quasar

Quasar payload

Description Indicator Process Target
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:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Enumerates physical storage devices

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:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Suspicious use of FindShellTrayWindow

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\SubDir\Client.exe N/A

Suspicious use of SendNotifyMessage

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\SubDir\Client.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 "Quasar Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f

C:\Users\Admin\AppData\Roaming\SubDir\Client.exe

"C:\Users\Admin\AppData\Roaming\SubDir\Client.exe"

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /create /tn "Quasar Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f

Network

Country Destination Domain Proto
N/A 192.168.0.18:4782 tcp
N/A 192.168.0.18:4782 tcp
US 8.8.8.8:53 8.8.8.8.in-addr.arpa udp
N/A 192.168.0.18:4782 tcp
N/A 192.168.0.18:4782 tcp
N/A 192.168.0.18:4782 tcp
N/A 192.168.0.18:4782 tcp

Files

memory/1260-0-0x00007FFD38193000-0x00007FFD38195000-memory.dmp

memory/1260-1-0x0000000000E50000-0x0000000001174000-memory.dmp

memory/1260-2-0x00007FFD38190000-0x00007FFD38C52000-memory.dmp

C:\Users\Admin\AppData\Roaming\SubDir\Client.exe

MD5 671df8e1c2f83f10f1cfb3f447299806
SHA1 9586ee12e49e5fbac96adfd5f3d59e4dfb8393f0
SHA256 597a26bc8399acff834bbce2ccbe7d5bab0e190e7f9163c2bce5feacc7f77ee9
SHA512 097a01e399d7527b0fc2bf952e7153d56b255897ef3f219cbd32938072d4ea66e62894d66f6b0ca80fbfda5c02738497d60c2ea415b0f900941a9c3121619690

memory/1260-8-0x00007FFD38190000-0x00007FFD38C52000-memory.dmp

memory/3616-9-0x00007FFD38190000-0x00007FFD38C52000-memory.dmp

memory/3616-10-0x00007FFD38190000-0x00007FFD38C52000-memory.dmp

memory/3616-11-0x000000001C000000-0x000000001C050000-memory.dmp

memory/3616-12-0x000000001C110000-0x000000001C1C2000-memory.dmp

memory/3616-13-0x00007FFD38190000-0x00007FFD38C52000-memory.dmp

Analysis: behavioral4

Detonation Overview

Submitted

2024-11-03 07:12

Reported

2024-11-03 07:16

Platform

win7-20241010-en

Max time kernel

122s

Max time network

129s

Command Line

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

Signatures

Quasar RAT

trojan spyware quasar

Quasar family

quasar

Quasar payload

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

Scheduled Task/Job: Scheduled Task

persistence execution
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 2368 wrote to memory of 2308 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\schtasks.exe
PID 2368 wrote to memory of 2308 N/A C:\Users\Admin\AppData\Local\Temp\Client-built.exe C:\Windows\system32\schtasks.exe
PID 2368 wrote to memory of 2308 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:\Windows\system32\schtasks.exe

"schtasks" /create /tn "Quasar Client Startup" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe" /rl HIGHEST /f

Network

N/A

Files

memory/2368-0-0x000007FEF5653000-0x000007FEF5654000-memory.dmp

memory/2368-1-0x0000000000F20000-0x0000000001244000-memory.dmp

memory/2368-2-0x000007FEF5650000-0x000007FEF603C000-memory.dmp

memory/2368-4-0x000007FEF5653000-0x000007FEF5654000-memory.dmp

memory/2368-5-0x000007FEF5650000-0x000007FEF603C000-memory.dmp