quasar | 3963fc0a539aff38363c40398e825669c36293b20ecac08baa05bcf69b7f785f

General

Target

Client-built.exe
Size

3.1MB
MD5

1fc150ca8d96e8cfccdbcc73dcc91f1e
SHA1

84a7512da60a13ffa44ece35a882a124abe15b38
SHA256

3963fc0a539aff38363c40398e825669c36293b20ecac08baa05bcf69b7f785f
SHA512

2ff46cd3ea3724c3fa32891ffa391cc10d11f7157d003f8cde97597071508b1d4de33fd9014582120ad12a11c72bdb553c39fbbabe251bf85843ba8a309f90bb
SSDEEP

49152:HvyI22SsaNYfdPBldt698dBcjHWARJ6FbR3LoGduyTHHB72eh2NT:Hvf22SsaNYfdPBldt6+dBcjHWARJ6X

Score

10^/10

quasar office04 spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

C2

98.218.3.74:4782

Mutex

3808ff71-c2df-4538-8d66-6459677347c3

Attributes

encryption_key
24BCF759F51AE66E5C4BF0A521BA79747D6F977F
install_name
Client.exe
log_directory
Logs
reconnect_delay
3000
startup_key
Quasar 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/3160-1-0x0000000000D10000-0x0000000001034000-memory.dmp	family_quasar
behavioral1/files/0x001e00000002ae06-6.dat	family_quasar

Executes dropped EXE 1 IoCs

pid	Process
3668	Client.exe

Modifies registry class 1 IoCs

description	ioc	Process
Key created	\REGISTRY\USER\S-1-5-21-2969674418-3952479498-2422112087-1000_Classes\Local Settings\MuiCache	MiniSearchHost.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
2424	schtasks.exe
4148	schtasks.exe

Suspicious use of AdjustPrivilegeToken 2 IoCs

description	pid	Process
Token: SeDebugPrivilege	3160	Client-built.exe
Token: SeDebugPrivilege	3668	Client.exe

Suspicious use of SetWindowsHookEx 2 IoCs

pid	Process
3668	Client.exe
2076	MiniSearchHost.exe

Suspicious use of WriteProcessMemory 6 IoCs

description	pid	Process	procid_target
PID 3160 wrote to memory of 4148	3160	Client-built.exe	79
PID 3160 wrote to memory of 4148	3160	Client-built.exe	79
PID 3160 wrote to memory of 3668	3160	Client-built.exe	81
PID 3160 wrote to memory of 3668	3160	Client-built.exe	81
PID 3668 wrote to memory of 2424	3668	Client.exe	82
PID 3668 wrote to memory of 2424	3668	Client.exe	82

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⤵
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:3160
- 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
  2⤵
  - Scheduled Task/Job: Scheduled Task
  PID:4148
- C:\Users\Admin\AppData\Roaming\SubDir\Client.exe
  "C:\Users\Admin\AppData\Roaming\SubDir\Client.exe"
  2⤵
  - Executes dropped EXE
  - Suspicious use of AdjustPrivilegeToken
  - Suspicious use of SetWindowsHookEx
  - Suspicious use of WriteProcessMemory
  PID:3668
- - 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
    3⤵
    - Scheduled Task/Job: Scheduled Task
    PID:2424

C:\Windows\SystemApps\MicrosoftWindows.Client.CBS_cw5n1h2txyewy\MiniSearchHost.exe
"C:\Windows\SystemApps\MicrosoftWindows.Client.CBS_cw5n1h2txyewy\MiniSearchHost.exe" -ServerName:MiniSearchUI.AppXj3y73at8fy1htwztzxs68sxx1v7cksp7.mca
1⤵
- Modifies registry class
- Suspicious use of SetWindowsHookEx
PID:2076

Network

MITRE ATT&CK Enterprise v15

Reconnaissance

Resource Development

Initial Access

Execution

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Persistence

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Privilege Escalation

Scheduled Task/Job

1

T1053

Scheduled Task

1

T1053.005

Defense Evasion

Credential Access

Discovery

Query Registry

1

T1012

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

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Downloads

C:\Users\Admin\AppData\Local\Packages\MicrosoftWindows.Client.CBS_cw5n1h2txyewy\TempState\SearchHoverUnifiedTileModelCache.dat

Filesize
23KB

MD5
49b77dfea4ac37067f686fd561c698d6

SHA1
59e60be76cba22e2956c9962b932d6efee041aff

SHA256
faba83540d4bf94dbf3344d29be1f619d70fcd0bc0a3c758bffb9ea34f59a636

SHA512
d32027d5d2ac8f0478e97770a22d387b95eb1de0f7ae5196ee0b6ab4ff3a4edfc3d124323e707d90ffab39050dded4ae0a593c20345f22c4c615e398fc92c06f

Download Submit
C:\Users\Admin\AppData\Local\Packages\MicrosoftWindows.Client.CBS_cw5n1h2txyewy\TempState\SearchHoverUnifiedTileModelCache.dat

Filesize
23KB

MD5
b2b304f54a7b8454d37e7fc65f8fee6a

SHA1
4927f81285dfca8e8c3434cb5e7b4f7b1bb31352

SHA256
29b02944da7a0fb17fdb7004902b6de71e8b759875867ca7cc4f3fac0f916e46

SHA512
f6781bcf31352605848c376d387f37bc7be1039f3fd9ad12354036361bff677b5269f6e7f78ed6d9a351f9fc273786e45b28d23eef38f18f4ba254e59c4d63bb

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

Filesize
3.1MB

MD5
1fc150ca8d96e8cfccdbcc73dcc91f1e

SHA1
84a7512da60a13ffa44ece35a882a124abe15b38

SHA256
3963fc0a539aff38363c40398e825669c36293b20ecac08baa05bcf69b7f785f

SHA512
2ff46cd3ea3724c3fa32891ffa391cc10d11f7157d003f8cde97597071508b1d4de33fd9014582120ad12a11c72bdb553c39fbbabe251bf85843ba8a309f90bb

Download Submit
memory/3160-0-0x00007FFE68533000-0x00007FFE68535000-memory.dmp

Filesize
8KB

Download
memory/3160-1-0x0000000000D10000-0x0000000001034000-memory.dmp

Filesize
3.1MB

Download
memory/3160-2-0x00007FFE68530000-0x00007FFE68FF2000-memory.dmp

Filesize
10.8MB

Download
memory/3160-10-0x00007FFE68530000-0x00007FFE68FF2000-memory.dmp

Filesize
10.8MB

Download
memory/3668-9-0x00007FFE68530000-0x00007FFE68FF2000-memory.dmp

Filesize
10.8MB

Download
memory/3668-11-0x00007FFE68530000-0x00007FFE68FF2000-memory.dmp

Filesize
10.8MB

Download
memory/3668-12-0x000000001BE70000-0x000000001BEC0000-memory.dmp

Filesize
320KB

Download
memory/3668-13-0x000000001C7C0000-0x000000001C872000-memory.dmp

Filesize
712KB

Download
memory/3668-14-0x00007FFE68530000-0x00007FFE68FF2000-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