Analysis
- max time kernel
122s - max time network
157s - platform
windows10-2004_x64 - resource
win10v2004-20240226-en - resource tags
- submitted
31/03/2024, 00:33
General
- Target Client-built.exe
- Size 3.1MB
- Sample240331-av6tzsah64
- SHA256 f2e04196e1353ad216e077e0aeb2e1ab8ee93b8b16b205422b4cc6d8adc50cc2
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 RAT
Quasar is an open source Remote Access Tool.
- Quasar payload 2 IoCs
- Executes dropped EXE 1 IoCs
- Creates scheduled task(s) 1 TTPs 2 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
- Suspicious use of AdjustPrivilegeToken 2 IoCs
- Suspicious use of SetWindowsHookEx 1 IoCs
- Suspicious use of WriteProcessMemory 6 IoCs
- 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
-
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)
-
-
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
-
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)
-
-
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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=3900 --field-trial-handle=3084,i,11997299123381683778,5904351605020331957,262144 --variations-seed-version /prefetch:81⤵
Network
MITRE ATT&CK Enterprise v15
Replay Monitor
Loading Replay Monitor...
Downloads
WOS64UPD.exe
memory/1592-10-0x00007FF8EF720000-0x00007FF8F01E1000-memory.dmp
memory/1592-2-0x0000000002760000-0x0000000002770000-memory.dmp
memory/1592-1-0x00007FF8EF720000-0x00007FF8F01E1000-memory.dmp
memory/1592-0-0x0000000000350000-0x0000000000674000-memory.dmp
memory/3884-7-0x00007FF8EF720000-0x00007FF8F01E1000-memory.dmp
memory/3884-9-0x000000001B310000-0x000000001B320000-memory.dmp
memory/3884-11-0x000000001B280000-0x000000001B2D0000-memory.dmp
memory/3884-12-0x000000001BED0000-0x000000001BF82000-memory.dmp
memory/3884-15-0x000000001BE30000-0x000000001BE42000-memory.dmp
memory/3884-16-0x000000001BE90000-0x000000001BECC000-memory.dmp
memory/3884-17-0x00007FF8EF720000-0x00007FF8F01E1000-memory.dmp
memory/3884-18-0x000000001B310000-0x000000001B320000-memory.dmp