quasar | a72f77cddbd993e606115287c8806adbd6b08e3217a6c6ea9a8f31fdca56c317

Analysis

max time kernel
149s
max time network
150s
platform
windows10-2004_x64
resource
win10v2004-20240508-en
resource tags

arch:x64arch:x86image:win10v2004-20240508-enlocale:en-usos:windows10-2004-x64system
submitted
23-06-2024 14:31

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General

Target

Client-built.exe
Size

3.1MB
MD5

e010924db36ba5093382221cdf0c89df
SHA1

09e2ab5a296e5500001cee9481b8a066b1f400e5
SHA256

a72f77cddbd993e606115287c8806adbd6b08e3217a6c6ea9a8f31fdca56c317
SHA512

1c3bf5fd4a36438376416ba7c7758929403a74d37805ff283aede3586bbd2e4aa2b41bc5aa9e79523e1940bdeafcb60d15c74a88d7de82a5f21dbd507591a0f0
SSDEEP

49152:3vHI22SsaNYfdPBldt698dBcjHDJSC1J6loGdsTHHB72eh2NT:3vo22SsaNYfdPBldt6+dBcjHDJSv

Score

10^/10

quasar office04 spyware trojan

Malware Config

Extracted

Family

quasar

Version

1.4.1

Botnet

Office04

192.168.26.243:4782

Mutex

51d612b2-dcb5-4477-9ee7-748df2f891d3

Attributes

encryption_key
D7CE15708C398D1F0A3B43032DE529C00B9A8B5F
install_name
windowsupdater.exe
log_directory
Logs
reconnect_delay
3000
startup_key
msedge.exe
subdirectory
Win64

Signatures

Quasar RAT
Quasar is an open source Remote Access Tool.
trojan spyware quasar
Quasar payload 2 IoCs

Processes:

resource yara_rule

behavioral2/memory/2376-1-0x0000000000560000-0x0000000000884000-memory.dmp family_quasar
C:\Windows\system32\Win64\windowsupdater.exe family_quasar
Executes dropped EXE 1 IoCs

Processes:

windowsupdater.exe

pid process

4920 windowsupdater.exe

resource	yara_rule
behavioral2/memory/2376-1-0x0000000000560000-0x0000000000884000-memory.dmp	family_quasar
C:\Windows\system32\Win64\windowsupdater.exe	family_quasar

pid	process
4920	windowsupdater.exe

Drops file in System32 directory 5 IoCs

Processes:

Client-built.exewindowsupdater.exe

description	ioc	process
File created	C:\Windows\system32\Win64\windowsupdater.exe	Client-built.exe
File opened for modification	C:\Windows\system32\Win64\windowsupdater.exe	Client-built.exe
File opened for modification	C:\Windows\system32\Win64	Client-built.exe
File opened for modification	C:\Windows\system32\Win64\windowsupdater.exe	windowsupdater.exe
File opened for modification	C:\Windows\system32\Win64	windowsupdater.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

Processes:

schtasks.exeschtasks.exe

pid process

2556 schtasks.exe
2800 schtasks.exe
Suspicious use of AdjustPrivilegeToken 2 IoCs

Processes:

Client-built.exewindowsupdater.exe

description pid process

Token: SeDebugPrivilege 2376 Client-built.exe
Token: SeDebugPrivilege 4920 windowsupdater.exe
Suspicious use of SetWindowsHookEx 1 IoCs

Processes:

windowsupdater.exe

pid process

4920 windowsupdater.exe

pid	process
2556	schtasks.exe
2800	schtasks.exe

description	pid	process
Token: SeDebugPrivilege	2376	Client-built.exe
Token: SeDebugPrivilege	4920	windowsupdater.exe

pid	process
4920	windowsupdater.exe

Suspicious use of WriteProcessMemory 6 IoCs

Processes:

Client-built.exewindowsupdater.exe

description	pid	process	target process
PID 2376 wrote to memory of 2800	2376	Client-built.exe	schtasks.exe
PID 2376 wrote to memory of 2800	2376	Client-built.exe	schtasks.exe
PID 2376 wrote to memory of 4920	2376	Client-built.exe	windowsupdater.exe
PID 2376 wrote to memory of 4920	2376	Client-built.exe	windowsupdater.exe
PID 4920 wrote to memory of 2556	4920	windowsupdater.exe	schtasks.exe
PID 4920 wrote to memory of 2556	4920	windowsupdater.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-built.exe
"C:\Users\Admin\AppData\Local\Temp\Client-built.exe"
1⤵
- Drops file in System32 directory
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:2376

C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "msedge.exe" /sc ONLOGON /tr "C:\Windows\system32\Win64\windowsupdater.exe" /rl HIGHEST /f
2⤵
- Scheduled Task/Job: Scheduled Task
PID:2800

C:\Windows\system32\Win64\windowsupdater.exe
"C:\Windows\system32\Win64\windowsupdater.exe"
2⤵
- Executes dropped EXE
- Drops file in System32 directory
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:4920

C:\Windows\SYSTEM32\schtasks.exe
"schtasks" /create /tn "msedge.exe" /sc ONLOGON /tr "C:\Windows\system32\Win64\windowsupdater.exe" /rl HIGHEST /f
3⤵
- Scheduled Task/Job: Scheduled Task
PID:2556

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 --field-trial-handle=4084,i,9746875443948590908,1444894342962555245,262144 --variations-seed-version --mojo-platform-channel-handle=4352 /prefetch:8
1⤵
PID:3680

C:\Windows\System32\rundll32.exe
C:\Windows\System32\rundll32.exe C:\Windows\System32\shell32.dll,SHCreateLocalServerRunDll {9aa46009-3ce0-458a-a354-715610a075e6} -Embedding
1⤵
PID:3436

Network

MITRE ATT&CK Matrix ATT&CK v13

Replay Monitor

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Downloads

C:\Windows\system32\Win64\windowsupdater.exe
Filesize
3.1MB

MD5
e010924db36ba5093382221cdf0c89df

SHA1
09e2ab5a296e5500001cee9481b8a066b1f400e5

SHA256
a72f77cddbd993e606115287c8806adbd6b08e3217a6c6ea9a8f31fdca56c317

SHA512
1c3bf5fd4a36438376416ba7c7758929403a74d37805ff283aede3586bbd2e4aa2b41bc5aa9e79523e1940bdeafcb60d15c74a88d7de82a5f21dbd507591a0f0

Download Submit
memory/2376-0-0x00007FFB408D3000-0x00007FFB408D5000-memory.dmp

Filesize
8KB

Download
memory/2376-1-0x0000000000560000-0x0000000000884000-memory.dmp

Filesize
3.1MB

Download
memory/2376-2-0x00007FFB408D0000-0x00007FFB41391000-memory.dmp

Filesize
10.8MB

Download
memory/2376-9-0x00007FFB408D0000-0x00007FFB41391000-memory.dmp

Filesize
10.8MB

Download
memory/4920-10-0x00007FFB408D0000-0x00007FFB41391000-memory.dmp

Filesize
10.8MB

Download
memory/4920-11-0x00007FFB408D0000-0x00007FFB41391000-memory.dmp

Filesize
10.8MB

Download
memory/4920-12-0x000000001B8D0000-0x000000001B920000-memory.dmp

Filesize
320KB

Download
memory/4920-13-0x000000001C4F0000-0x000000001C5A2000-memory.dmp

Filesize
712KB

Download
memory/4920-14-0x00007FFB408D0000-0x00007FFB41391000-memory.dmp

Filesize
10.8MB

Download
memory/4920-15-0x000000001CE20000-0x000000001D348000-memory.dmp

Filesize
5.2MB

Download