quasar | b2ebc3a634719e1727dcae13f9a4f5df3d89b89718cfd0b2886a971a08b55e77

General

Target

Client-abuilt.exe
Size

3.3MB
MD5

fe6bb1f615029c7e339444cbc41706bb
SHA1

cabd13e4e04ef81687812f8680e55e048ee75bd7
SHA256

b2ebc3a634719e1727dcae13f9a4f5df3d89b89718cfd0b2886a971a08b55e77
SHA512

90b15572b73bb065f8cc38a2ca1dbe8ee73991c3693c49f96cda8652d89b010199f4f152b53ae5a7de1a3b13877d301f724ff454e9187950053f7735849e7e82
SSDEEP

49152:3v+I22SsaNYfdPBldt698dBcjHQr0hrTavJSZoGdbTHHB72eh2NTDZqS:3vz22SsaNYfdPBldt6+dBcjHdTB

Score

10^/10

quasar office01 spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office01

C2

198.7.62.204:4782

192.168.1.1:4782

Mutex

02b9c972-8b55-4d55-b7c4-09a1f00ff400

Attributes

encryption_key
5BF0703F288C43118835CAF4D1A6879C29016FB3
install_name
Client.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 payload 2 IoCs

Processes:

resource	yara_rule
behavioral2/memory/4380-0-0x0000000000010000-0x0000000000358000-memory.dmp	family_quasar
C:\Windows\System32\SubDir\Client.exe	family_quasar

Executes dropped EXE 1 IoCs

Processes:

Client.exe

pid process

4084 Client.exe

pid	process
4084	Client.exe

Drops file in System32 directory 5 IoCs

Processes:

Client-abuilt.exeClient.exe

description	ioc	process
File created	C:\Windows\system32\SubDir\Client.exe	Client-abuilt.exe
File opened for modification	C:\Windows\system32\SubDir\Client.exe	Client-abuilt.exe
File opened for modification	C:\Windows\system32\SubDir	Client-abuilt.exe
File opened for modification	C:\Windows\system32\SubDir\Client.exe	Client.exe
File opened for modification	C:\Windows\system32\SubDir	Client.exe

Creates scheduled task(s) 1 TTPs 2 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
persistence

Scheduled Task/Job
T1053

Processes:

schtasks.exeschtasks.exe

pid process

1432 schtasks.exe
2940 schtasks.exe
Suspicious use of AdjustPrivilegeToken 2 IoCs

Processes:

Client-abuilt.exeClient.exe

description pid process

Token: SeDebugPrivilege 4380 Client-abuilt.exe
Token: SeDebugPrivilege 4084 Client.exe
Suspicious use of SetWindowsHookEx 1 IoCs

Processes:

Client.exe

pid process

4084 Client.exe

pid	process
1432	schtasks.exe
2940	schtasks.exe

description	pid	process
Token: SeDebugPrivilege	4380	Client-abuilt.exe
Token: SeDebugPrivilege	4084	Client.exe

pid	process
4084	Client.exe

Suspicious use of WriteProcessMemory 6 IoCs

Processes:

Client-abuilt.exeClient.exe

description	pid	process	target process
PID 4380 wrote to memory of 1432	4380	Client-abuilt.exe	schtasks.exe
PID 4380 wrote to memory of 1432	4380	Client-abuilt.exe	schtasks.exe
PID 4380 wrote to memory of 4084	4380	Client-abuilt.exe	Client.exe
PID 4380 wrote to memory of 4084	4380	Client-abuilt.exe	Client.exe
PID 4084 wrote to memory of 2940	4084	Client.exe	schtasks.exe
PID 4084 wrote to memory of 2940	4084	Client.exe	schtasks.exe

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-abuilt.exe
"C:\Users\Admin\AppData\Local\Temp\Client-abuilt.exe"
1⤵
- Drops file in System32 directory
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:4380

C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\Client.exe" /rl HIGHEST /f
2⤵
- Creates scheduled task(s)
PID:1432

C:\Windows\system32\SubDir\Client.exe
"C:\Windows\system32\SubDir\Client.exe"
2⤵
- Executes dropped EXE
- Drops file in System32 directory
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:4084

C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "Client Startup" /sc ONLOGON /tr "C:\Windows\system32\SubDir\Client.exe" /rl HIGHEST /f
3⤵
- Creates scheduled task(s)
PID:2940

C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe
"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" --type=utility --utility-sub-type=asset_store.mojom.AssetStoreService --lang=en-US --service-sandbox-type=asset_store_service --no-appcompat-clear --mojo-platform-channel-handle=3696 --field-trial-handle=3192,i,2785050981002401924,4037047756083432660,262144 --variations-seed-version /prefetch:8
1⤵
PID:2444

Network

MITRE ATT&CK Matrix ATT&CK v13

Initial Access

Execution

Scheduled Task/Job

1

T1053

Persistence

Scheduled Task/Job

1

T1053

Privilege Escalation

Scheduled Task/Job

1

T1053

Defense Evasion

Credential Access

Discovery

Query Registry

1

T1012

Lateral Movement

Collection

Exfiltration

Command and Control

Impact

Resource Development

Reconnaissance

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Downloads

C:\Windows\System32\SubDir\Client.exe
Filesize
3.3MB

MD5
fe6bb1f615029c7e339444cbc41706bb

SHA1
cabd13e4e04ef81687812f8680e55e048ee75bd7

SHA256
b2ebc3a634719e1727dcae13f9a4f5df3d89b89718cfd0b2886a971a08b55e77

SHA512
90b15572b73bb065f8cc38a2ca1dbe8ee73991c3693c49f96cda8652d89b010199f4f152b53ae5a7de1a3b13877d301f724ff454e9187950053f7735849e7e82

Download Submit
memory/4084-9-0x00007FFED71B0000-0x00007FFED7C71000-memory.dmp

Filesize
10.8MB

Download
memory/4084-10-0x000000001B400000-0x000000001B410000-memory.dmp

Filesize
64KB

Download
memory/4084-12-0x000000001C0A0000-0x000000001C0F0000-memory.dmp

Filesize
320KB

Download
memory/4084-13-0x000000001C1B0000-0x000000001C262000-memory.dmp

Filesize
712KB

Download
memory/4084-14-0x00007FFED71B0000-0x00007FFED7C71000-memory.dmp

Filesize
10.8MB

Download
memory/4084-15-0x000000001B400000-0x000000001B410000-memory.dmp

Filesize
64KB

Download
memory/4380-0-0x0000000000010000-0x0000000000358000-memory.dmp

Filesize
3.3MB

Download
memory/4380-1-0x00007FFED71B0000-0x00007FFED7C71000-memory.dmp

Filesize
10.8MB

Download
memory/4380-2-0x000000001AF40000-0x000000001AF50000-memory.dmp

Filesize
64KB

Download
memory/4380-11-0x00007FFED71B0000-0x00007FFED7C71000-memory.dmp

Filesize
10.8MB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Matrix ATT&CK v13

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