Analysis
- max time kernel
148s - max time network
161s - platform
windows10_x64 - resource
win10v20210408 - submitted
31/08/2021, 06:49
General
- Target 41b5691a9272ab9dcb87a5f3f106da073fc3d2c4aea1abd78ac7b3af4cbbffdd.exe
- Size 799KB
- Sample210831-4c3gef4was
- SHA256 41b5691a9272ab9dcb87a5f3f106da073fc3d2c4aea1abd78ac7b3af4cbbffdd
Malware Config
Extracted
-
asyncrat
-
0.5.7B
-
null:null
-
AsyncMutex_6SI8OkPnk
-
aes_key
dDhvNMBYIS0cSEdqEZsTWnat4JCbi1fh
-
anti_detection
false
-
autorun
true
-
bdos
false
-
delay
ASE_2
-
host
null
-
hwid
3
- install_file
-
install_folder
%AppData%
-
mutex
AsyncMutex_6SI8OkPnk
-
pastebin_config
https://aa.larinax999.repl.co
-
port
null
-
version
0.5.7B
Signatures
- AsyncRat
AsyncRAT is designed to remotely monitor and control other computers.
- Async RAT payload 4 IoCs
- Executes dropped EXE 3 IoCs
- Suspicious Office macro 1 IoCs
Office document equipped with macros.
- Checks computer location settings 2 TTPs 1 IoCs
Looks up country code configured in the registry, likely geofence.
- Adds Run key to start application 2 TTPs 1 IoCs
- Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.
- Checks processor information in registry 2 TTPs 3 IoCs
Processor information is often read in order to detect sandboxing environments.
- Creates scheduled task(s) 1 TTPs 1 IoCs
Schtasks is often used by malware for persistence or to perform post-infection execution.
- Delays execution with timeout.exe 1 IoCs
- Enumerates system info in registry 2 TTPs 3 IoCs
- Modifies registry class 1 IoCs
- Suspicious behavior: AddClipboardFormatListener 1 IoCs
- Suspicious behavior: EnumeratesProcesses 13 IoCs
- Suspicious use of AdjustPrivilegeToken 2 IoCs
- Suspicious use of SetWindowsHookEx 5 IoCs
- Suspicious use of WriteProcessMemory 21 IoCs
Processes
-
C:\Users\Admin\AppData\Local\Temp\41b5691a9272ab9dcb87a5f3f106da073fc3d2c4aea1abd78ac7b3af4cbbffdd.exe"C:\Users\Admin\AppData\Local\Temp\41b5691a9272ab9dcb87a5f3f106da073fc3d2c4aea1abd78ac7b3af4cbbffdd.exe"1⤵
- Checks computer location settings
- Adds Run key to start application
- Modifies registry class
- Suspicious use of WriteProcessMemory
-
C:\Users\Admin\AppData\Local\Temp\._cache_41b5691a9272ab9dcb87a5f3f106da073fc3d2c4aea1abd78ac7b3af4cbbffdd.exe"C:\Users\Admin\AppData\Local\Temp\._cache_41b5691a9272ab9dcb87a5f3f106da073fc3d2c4aea1abd78ac7b3af4cbbffdd.exe"2⤵
- Executes dropped EXE
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
-
C:\Windows\SysWOW64\cmd.exe"C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "MsMpEng" /tr '"C:\Users\Admin\AppData\Roaming\MsMpEng.exe"' & exit3⤵
- Suspicious use of WriteProcessMemory
-
C:\Windows\SysWOW64\schtasks.exeschtasks /create /f /sc onlogon /rl highest /tn "MsMpEng" /tr '"C:\Users\Admin\AppData\Roaming\MsMpEng.exe"'4⤵
- Creates scheduled task(s)
-
-
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C:\Windows\SysWOW64\cmd.exeC:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp1907.tmp.bat""3⤵
- Suspicious use of WriteProcessMemory
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C:\Windows\SysWOW64\timeout.exetimeout 34⤵
- Delays execution with timeout.exe
-
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C:\Users\Admin\AppData\Roaming\MsMpEng.exe"C:\Users\Admin\AppData\Roaming\MsMpEng.exe"4⤵
- Executes dropped EXE
- Suspicious use of AdjustPrivilegeToken
-
-
-
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C:\ProgramData\Synaptics\Synaptics.exe"C:\ProgramData\Synaptics\Synaptics.exe" InjUpdate2⤵
- Executes dropped EXE
-
-
C:\Program Files\Microsoft Office\Root\Office16\EXCEL.EXE"C:\Program Files\Microsoft Office\Root\Office16\EXCEL.EXE" /automation -Embedding1⤵
- Checks processor information in registry
- Enumerates system info in registry
- Suspicious behavior: AddClipboardFormatListener
- Suspicious use of SetWindowsHookEx
Network
MITRE ATT&CK Enterprise v6
Replay Monitor
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Downloads
memory/764-114-0x0000000000720000-0x0000000000721000-memory.dmp
memory/2820-136-0x00007FF999990000-0x00007FF9999A0000-memory.dmp
memory/2820-144-0x00007FF9BAB10000-0x00007FF9BBBFE000-memory.dmp
memory/2820-145-0x00007FF9B8C10000-0x00007FF9BAB05000-memory.dmp
memory/2820-130-0x00007FF999990000-0x00007FF9999A0000-memory.dmp
memory/2820-135-0x00007FF999990000-0x00007FF9999A0000-memory.dmp
memory/2820-132-0x00007FF999990000-0x00007FF9999A0000-memory.dmp
memory/2820-122-0x00007FF7A98D0000-0x00007FF7ACE86000-memory.dmp
memory/2820-134-0x00007FF999990000-0x00007FF9999A0000-memory.dmp
memory/2964-121-0x00000000021C0000-0x00000000021C1000-memory.dmp
memory/3652-146-0x0000000004D50000-0x0000000004D51000-memory.dmp
memory/3652-154-0x0000000005EA0000-0x0000000005EA1000-memory.dmp
memory/3652-155-0x00000000055E0000-0x00000000055E1000-memory.dmp
memory/4044-125-0x00000000056A0000-0x00000000056A1000-memory.dmp
memory/4044-123-0x0000000000D40000-0x0000000000D41000-memory.dmp
memory/4044-126-0x0000000005750000-0x0000000005751000-memory.dmp