Malware Analysis Report

2025-01-18 04:34

Sample ID 231227-2sfcsshchk
Target Client-built.exe
SHA256 37d30f9f28f61ffeb1a8f041167966dc075c62b123d832e738548cd4909d54fd
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 Overview

score
10/10

SHA256

37d30f9f28f61ffeb1a8f041167966dc075c62b123d832e738548cd4909d54fd

Threat Level: Known bad

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

Malicious Activity Summary

office04 quasar spyware trojan

Quasar family

Quasar payload

Quasar RAT

Executes dropped EXE

Unsigned PE

Suspicious use of AdjustPrivilegeToken

Suspicious use of WriteProcessMemory

Creates scheduled task(s)

Uses Task Scheduler COM API

MITRE ATT&CK

Analysis: static1

Detonation Overview

Reported

2023-12-27 22:50

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

2023-12-27 22:50

Reported

2023-12-27 22:53

Platform

win10v2004-20231215-en

Max time kernel

148s

Max time network

152s

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

Executes dropped EXE

Description Indicator Process Target
N/A N/A C:\Users\Admin\AppData\Roaming\Realtek HD Audio Universal Service\RtkAudUService64.exe N/A

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

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\Realtek HD Audio Universal Service\RtkAudUService64.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:\Users\Admin\AppData\Roaming\Realtek HD Audio Universal Service\RtkAudUService64.exe

"C:\Users\Admin\AppData\Roaming\Realtek HD Audio Universal Service\RtkAudUService64.exe"

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /create /tn "Realtek HD Audio Universal Service" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Realtek HD Audio Universal Service\RtkAudUService64.exe" /rl HIGHEST /f

C:\Windows\SYSTEM32\schtasks.exe

"schtasks" /create /tn "Realtek HD Audio Universal Service" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Realtek HD Audio Universal Service\RtkAudUService64.exe" /rl HIGHEST /f

Network

Country Destination Domain Proto
US 8.8.8.8:53 g.bing.com udp
US 8.8.8.8:53 59.128.231.4.in-addr.arpa udp
US 8.8.8.8:53 22.177.190.20.in-addr.arpa udp
N/A 192.168.178.197:4782 tcp
US 8.8.8.8:53 95.221.229.192.in-addr.arpa udp
US 204.79.197.200:443 g.bing.com tcp
US 8.8.8.8:53 200.197.79.204.in-addr.arpa udp
US 8.8.8.8:53 9.228.82.20.in-addr.arpa udp
N/A 192.168.178.197:4782 tcp
US 8.8.8.8:53 173.178.17.96.in-addr.arpa udp
US 8.8.8.8:53 134.71.91.104.in-addr.arpa udp
US 138.91.171.81:80 tcp
US 138.91.171.81:80 tcp
US 8.8.8.8:53 88.156.103.20.in-addr.arpa udp
N/A 192.168.178.197:4782 tcp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
GB 96.16.110.41:443 tcp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
N/A 52.165.164.15:443 tcp
N/A 51.104.136.2:443 tcp
N/A 51.104.136.2:443 tcp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
GB 96.16.110.114:80 tcp
US 20.231.121.79:80 tcp
N/A 192.168.178.197:4782 tcp
GB 96.16.110.114:80 tcp
US 8.8.8.8:53 udp
US 138.91.171.81:80 tcp
GB 96.16.110.114:80 tcp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
N/A 52.165.164.15:443 tcp
N/A 23.37.1.183:80 tcp
N/A 23.37.1.183:80 tcp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
US 8.8.8.8:53 48.229.111.52.in-addr.arpa udp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
N/A 20.54.110.119:443 tcp
N/A 52.165.164.15:443 tcp
US 8.8.8.8:53 udp
GB 96.17.178.173:80 tcp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
US 8.8.8.8:53 udp
N/A 192.168.178.197:4782 tcp
US 8.8.8.8:53 udp
US 204.79.197.200:443 g.bing.com tcp
US 204.79.197.200:443 g.bing.com tcp
US 204.79.197.200:443 g.bing.com tcp
US 204.79.197.200:443 g.bing.com tcp
US 204.79.197.200:443 g.bing.com tcp
N/A 192.168.178.197:4782 tcp
N/A 192.168.178.197:4782 tcp

Files

memory/5048-0-0x0000000000BD0000-0x0000000000EF4000-memory.dmp

memory/5048-1-0x00007FFE123D0000-0x00007FFE12E91000-memory.dmp

memory/5048-2-0x000000001BD40000-0x000000001BD50000-memory.dmp

memory/4224-10-0x00007FFE123D0000-0x00007FFE12E91000-memory.dmp

memory/4224-11-0x000000001B8A0000-0x000000001B8B0000-memory.dmp

memory/5048-9-0x00007FFE123D0000-0x00007FFE12E91000-memory.dmp

memory/4224-12-0x000000001BFF0000-0x000000001C040000-memory.dmp

memory/4224-13-0x000000001C100000-0x000000001C1B2000-memory.dmp

memory/4224-14-0x00007FFE123D0000-0x00007FFE12E91000-memory.dmp

memory/4224-15-0x000000001B8A0000-0x000000001B8B0000-memory.dmp