quasar | 835c6cbfdadec9581b69848bca95c1ac08838558bcbb781a54a2368d19c2a74c

Analysis

max time kernel
125s
max time network
151s
platform
windows11-21h2_x64
resource
win11-20241007-en
resource tags

arch:x64arch:x86image:win11-20241007-enlocale:en-usos:windows11-21h2-x64system
submitted
07/02/2025, 00:21

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General

Target

Client-built.exe
Size

3.2MB
MD5

274a62ce2c608c1012ae62ca1bf15bff
SHA1

94c43f6984f7823a62fc5aa850b242f00af312c2
SHA256

835c6cbfdadec9581b69848bca95c1ac08838558bcbb781a54a2368d19c2a74c
SHA512

8af65d5b1eca9db8f1ef9166f30bea7143652eae464d71f920ccac61427c1885b2a01b9e7e51365269449bd362ae924e8de4a6f466cc9ab851d797ff712b693f
SSDEEP

49152:wvAt62XlaSFNWPjljiFa2RoUYIeFwxNESEfk/iBLoGd2qTHHB72eh2NT:wvs62XlaSFNWPjljiFXRoUYILxiR

Score

10^/10

quasar office04 spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

12.75.114.52:4782

Mutex

d942a9a5-3785-41ac-a7db-12e8f1fb6c3d

Attributes

encryption_key
E662E8B331BDD6D3B27E1C68FDDE49A9178AEBE8
install_name
A.exe
log_directory
Logs
reconnect_delay
3000
startup_key
Client Startup
subdirectory
SubDir

Signatures

Quasar RAT
Quasar is an open source Remote Access Tool.
trojan spyware quasar
Quasar family
quasar

Quasar payload 2 IoCs

resource	yara_rule
behavioral1/memory/784-1-0x0000000000EC0000-0x00000000011F4000-memory.dmp	family_quasar
behavioral1/files/0x001c00000002ab76-6.dat	family_quasar

Executes dropped EXE 1 IoCs

pid	Process
4872	A.exe

Drops file in Program Files directory 5 IoCs

description	ioc	Process
File opened for modification	C:\Program Files\SubDir	A.exe
File created	C:\Program Files\SubDir\A.exe	Client-built.exe
File opened for modification	C:\Program Files\SubDir\A.exe	Client-built.exe
File opened for modification	C:\Program Files\SubDir	Client-built.exe
File opened for modification	C:\Program Files\SubDir\A.exe	A.exe

Scheduled Task/Job: Scheduled Task 1 TTPs 2 IoCs

Schtasks is often used by malware for persistence or to perform post-infection execution.

persistence execution

Scheduled Task

T1053.005

pid	Process
3160	schtasks.exe
2596	schtasks.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	784	Client-built.exe
Token: SeDebugPrivilege	4872	A.exe

Suspicious use of SetWindowsHookEx 1 IoCs

pid	Process
4872	A.exe

Suspicious use of WriteProcessMemory 6 IoCs

description	pid	Process	procid_target
PID 784 wrote to memory of 3160	784	Client-built.exe	77
PID 784 wrote to memory of 3160	784	Client-built.exe	77
PID 784 wrote to memory of 4872	784	Client-built.exe	79
PID 784 wrote to memory of 4872	784	Client-built.exe	79
PID 4872 wrote to memory of 2596	4872	A.exe	80
PID 4872 wrote to memory of 2596	4872	A.exe	80

Uses Task Scheduler COM API 1 TTPs
The Task Scheduler COM API can be used to schedule applications to run on boot or at set times.
persistence

Query Registry
T1012

C:\Users\Admin\AppData\Local\Temp\Client-built.exe
"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"
1⤵
- Drops file in Program Files directory
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:784
- C:\Windows\SYSTEM32\schtasks.exe
  "schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Program Files\SubDir\A.exe" /rl HIGHEST /f
  2⤵
  - Scheduled Task/Job: Scheduled Task
  PID:3160
- C:\Program Files\SubDir\A.exe
  "C:\Program Files\SubDir\A.exe"
  2⤵
  - Executes dropped EXE
  - Drops file in Program Files directory
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of SetWindowsHookEx
  - Suspicious use of WriteProcessMemory
  PID:4872
- - C:\Windows\SYSTEM32\schtasks.exe
    "schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Program Files\SubDir\A.exe" /rl HIGHEST /f
    3⤵
    - Scheduled Task/Job: Scheduled Task
    PID:2596

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Persistence

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Privilege Escalation

Scheduled Task/Job

T1053

Scheduled Task

T1053.005

Defense Evasion

Credential Access

Discovery

Query Registry

T1012

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Program Files\SubDir\A.exe

Filesize
3.2MB

MD5
274a62ce2c608c1012ae62ca1bf15bff

SHA1
94c43f6984f7823a62fc5aa850b242f00af312c2

SHA256
835c6cbfdadec9581b69848bca95c1ac08838558bcbb781a54a2368d19c2a74c

SHA512
8af65d5b1eca9db8f1ef9166f30bea7143652eae464d71f920ccac61427c1885b2a01b9e7e51365269449bd362ae924e8de4a6f466cc9ab851d797ff712b693f

Download Submit
memory/784-0-0x00007FFC462F3000-0x00007FFC462F5000-memory.dmp

Filesize
8KB

Download
memory/784-1-0x0000000000EC0000-0x00000000011F4000-memory.dmp

Filesize
3.2MB

Download
memory/784-2-0x00007FFC462F0000-0x00007FFC46DB2000-memory.dmp

Filesize
10.8MB

Download
memory/784-9-0x00007FFC462F0000-0x00007FFC46DB2000-memory.dmp

Filesize
10.8MB

Download
memory/4872-10-0x00007FFC462F0000-0x00007FFC46DB2000-memory.dmp

Filesize
10.8MB

Download
memory/4872-11-0x00007FFC462F0000-0x00007FFC46DB2000-memory.dmp

Filesize
10.8MB

Download
memory/4872-12-0x000000001C3C0000-0x000000001C410000-memory.dmp

Filesize
320KB

Download
memory/4872-13-0x000000001C4D0000-0x000000001C582000-memory.dmp

Filesize
712KB

Download
memory/4872-14-0x000000001CBC0000-0x000000001D0E8000-memory.dmp

Filesize
5.2MB

Download
memory/4872-15-0x00007FFC462F0000-0x00007FFC46DB2000-memory.dmp

Filesize
10.8MB

Download
memory/4872-16-0x00007FFC462F0000-0x00007FFC46DB2000-memory.dmp

Filesize
10.8MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Enterprise v15

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Downloads