Analysis
-
max time kernel
1726s -
max time network
1781s -
platform
windows11-21h2_x64 -
resource
win11-20240221-en -
resource tags
arch:x64arch:x86image:win11-20240221-enlocale:en-usos:windows11-21h2-x64system -
submitted
31/03/2024, 00:42
Behavioral task
behavioral1
Sample
Client-built.exe
Resource
win10-20240214-en
Behavioral task
behavioral2
Sample
Client-built.exe
Resource
win10v2004-20240226-en
General
-
Target
Client-built.exe
-
Size
3.1MB
-
MD5
57045c2bf3377b12aa5abce21cc0a99d
-
SHA1
217202ed404f25fc550ad70fd7066b0fe8773ef9
-
SHA256
f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2
-
SHA512
9ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e
-
SSDEEP
49152:Wv+I22SsaNYfdPBldt698dBcjHukuQPoGdhEQTHHB72eh2NT:Wvz22SsaNYfdPBldt6+dBcjHukuE
Malware Config
Extracted
quasar
1.4.1
Ratted
140.238.91.110:44867
be049c71-d631-4f68-8b3e-8e01081f2340
-
encryption_key
AA883CE7347A3543F81EBCDE3BBF3BFC9C60344E
-
install_name
WOS64UPD.exe
-
log_directory
Windows Update Logs
-
reconnect_delay
3000
-
startup_key
Windows Updater
-
subdirectory
Windows
Signatures
-
Quasar payload 2 IoCs
resource yara_rule behavioral3/memory/668-0-0x0000000000410000-0x0000000000734000-memory.dmp family_quasar behavioral3/files/0x0002000000029e10-5.dat family_quasar -
Executes dropped EXE 1 IoCs
pid Process 4500 WOS64UPD.exe -
Creates scheduled task(s) 1 TTPs 2 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
pid Process 2392 schtasks.exe 3228 schtasks.exe -
Suspicious use of AdjustPrivilegeToken 2 IoCs
description pid Process Token: SeDebugPrivilege 668 Client-built.exe Token: SeDebugPrivilege 4500 WOS64UPD.exe -
Suspicious use of SetWindowsHookEx 1 IoCs
pid Process 4500 WOS64UPD.exe -
Suspicious use of WriteProcessMemory 6 IoCs
description pid Process procid_target PID 668 wrote to memory of 2392 668 Client-built.exe 80 PID 668 wrote to memory of 2392 668 Client-built.exe 80 PID 668 wrote to memory of 4500 668 Client-built.exe 82 PID 668 wrote to memory of 4500 668 Client-built.exe 82 PID 4500 wrote to memory of 3228 4500 WOS64UPD.exe 83 PID 4500 wrote to memory of 3228 4500 WOS64UPD.exe 83 -
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.
Processes
-
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:668 -
C:\Windows\SYSTEM32\schtasks.exe"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f2⤵
- Creates scheduled task(s)
PID:2392
-
-
C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe"C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe"2⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of SetWindowsHookEx
- Suspicious use of WriteProcessMemory
PID:4500 -
C:\Windows\SYSTEM32\schtasks.exe"schtasks" /create /tn "Windows Updater" /sc ONLOGON /tr "C:\Users\Admin\AppData\Roaming\Windows\WOS64UPD.exe" /rl HIGHEST /f3⤵
- Creates scheduled task(s)
PID:3228
-
-
Network
MITRE ATT&CK Enterprise v15
Replay Monitor
Loading Replay Monitor...
Downloads
-
Filesize
3.1MB
MD557045c2bf3377b12aa5abce21cc0a99d
SHA1217202ed404f25fc550ad70fd7066b0fe8773ef9
SHA256f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2
SHA5129ab46cc194eeaabb75777457a01328f5a8d2ebf604efba0623575cf25c04e206e416ee72db17e3c92a9d363330f82fa3ce2aac64c2a4a61d4dce34d79b73366e