asyncrat | 932cb9cc50f478211994f9fff6e753e1ea56877326db099350b8f59b6c236d04

General

Target

AsyncClient.exe
Size

47KB
MD5

cd56336140a135c2262054ee149c1550
SHA1

8cae4cf270f01d89829c124f8a8883c0844d5443
SHA256

932cb9cc50f478211994f9fff6e753e1ea56877326db099350b8f59b6c236d04
SHA512

785280be15d4bd25245f74c2b5b770e6936655911626d4ed7895ac4ab943c2149e204d5b190c5a6308d2c0fb6075151120f16ecf46e0fa89cd7616b16ac5ba85
SSDEEP

768:muC0NTgoZqNYhWU58PnLmo2qr2OHcmUPIYo8USy80bHZbxBwgfgxIdAuj47ZGkB:muC0NTgmq12FmZYo8ubH3BLgMOISdIx

Score

10^/10

asyncrat default rat

Malware Config

Extracted

Family

asyncrat

Version

0.5.7B

Botnet

Default

C2

127.0.0.1:6606

127.0.0.1:7707

127.0.0.1:8808

Mutex

AsyncMutex_6SI8OkPnk

Attributes

delay
3
install
true
install_file
exe
install_folder
%AppData%

aes.plain

Signatures

AsyncRat
AsyncRAT is designed to remotely monitor and control other computers written in C#.
rat asyncrat

Async RAT payload 2 IoCs

rat

Processes:

resource	yara_rule
behavioral1/memory/1332-133-0x00000000002F0000-0x0000000000302000-memory.dmp	asyncrat
C:\Users\Admin\AppData\Roaming\exe	asyncrat

Checks computer location settings 2 TTPs 1 IoCs

Looks up country code configured in the registry, likely geofence.

Query Registry

T1012

System Information Discovery

T1082

Processes:

AsyncClient.exe

description	ioc	process
Key value queried	\REGISTRY\USER\S-1-5-21-1529757233-3489015626-3409890339-1000\Control Panel\International\Geo\Nation	AsyncClient.exe

Enumerates physical storage devices 1 TTPs
Attempts to interact with connected storage/optical drive(s). Likely ransomware behaviour.

System Information Discovery
T1082

Checks processor information in registry 2 TTPs 3 IoCs

Processor information is often read in order to detect sandboxing environments.

Query Registry

T1012

System Information Discovery

T1082

Processes:

WINWORD.EXE

description	ioc	process
Key opened	\REGISTRY\MACHINE\Hardware\Description\System\CentralProcessor\0	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\~MHz	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0\ProcessorNameString	WINWORD.EXE

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

Scheduled Task
T1053

Processes:

schtasks.exe

pid process

236 schtasks.exe
Delays execution with timeout.exe 1 IoCs
evasion

Processes:

timeout.exe

pid process

216 timeout.exe

pid	process
236	schtasks.exe

pid	process
216	timeout.exe

Enumerates system info in registry 2 TTPs 3 IoCs

Query Registry

T1012

System Information Discovery

T1082

Processes:

WINWORD.EXE

description	ioc	process
Key opened	\REGISTRY\MACHINE\Hardware\Description\System\BIOS	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemFamily	WINWORD.EXE
Key value queried	\REGISTRY\MACHINE\HARDWARE\DESCRIPTION\System\BIOS\SystemSKU	WINWORD.EXE

Modifies registry class 2 IoCs

Processes:

cmd.exeOpenWith.exe

description	ioc	process
Key created	\REGISTRY\USER\S-1-5-21-1529757233-3489015626-3409890339-1000_Classes\Local Settings	cmd.exe
Key created	\REGISTRY\USER\S-1-5-21-1529757233-3489015626-3409890339-1000_Classes\Local Settings	OpenWith.exe

Suspicious behavior: AddClipboardFormatListener 2 IoCs

Processes:

WINWORD.EXE

pid process

3964 WINWORD.EXE
3964 WINWORD.EXE

pid	process
3964	WINWORD.EXE
3964	WINWORD.EXE

Suspicious behavior: EnumeratesProcesses 23 IoCs

Processes:

AsyncClient.exe

pid	process
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe
1332	AsyncClient.exe

Suspicious use of AdjustPrivilegeToken 1 IoCs

Processes:

AsyncClient.exe

description pid process

Token: SeDebugPrivilege 1332 AsyncClient.exe

description	pid	process
Token: SeDebugPrivilege	1332	AsyncClient.exe

Suspicious use of SetWindowsHookEx 22 IoCs

Processes:

OpenWith.exeWINWORD.EXE

pid	process
3188	OpenWith.exe
3964	WINWORD.EXE
3964	WINWORD.EXE
3964	WINWORD.EXE
3964	WINWORD.EXE
3964	WINWORD.EXE
3188	OpenWith.exe
3188	OpenWith.exe
3964	WINWORD.EXE
3964	WINWORD.EXE
3188	OpenWith.exe
3188	OpenWith.exe
3964	WINWORD.EXE
3964	WINWORD.EXE
3188	OpenWith.exe
3188	OpenWith.exe
3964	WINWORD.EXE
3188	OpenWith.exe
3188	OpenWith.exe
3964	WINWORD.EXE
3964	WINWORD.EXE
3964	WINWORD.EXE

Suspicious use of WriteProcessMemory 12 IoCs

Processes:

AsyncClient.execmd.execmd.exe

description	pid	process	target process
PID 1332 wrote to memory of 3868	1332	AsyncClient.exe	cmd.exe
PID 1332 wrote to memory of 3868	1332	AsyncClient.exe	cmd.exe
PID 1332 wrote to memory of 3868	1332	AsyncClient.exe	cmd.exe
PID 1332 wrote to memory of 3860	1332	AsyncClient.exe	cmd.exe
PID 1332 wrote to memory of 3860	1332	AsyncClient.exe	cmd.exe
PID 1332 wrote to memory of 3860	1332	AsyncClient.exe	cmd.exe
PID 3868 wrote to memory of 236	3868	cmd.exe	schtasks.exe
PID 3868 wrote to memory of 236	3868	cmd.exe	schtasks.exe
PID 3868 wrote to memory of 236	3868	cmd.exe	schtasks.exe
PID 3860 wrote to memory of 216	3860	cmd.exe	timeout.exe
PID 3860 wrote to memory of 216	3860	cmd.exe	timeout.exe
PID 3860 wrote to memory of 216	3860	cmd.exe	timeout.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
Uses Volume Shadow Copy WMI provider
The Volume Shadow Copy service is used to manage backups/snapshots.
ransomware

C:\Users\Admin\AppData\Local\Temp\AsyncClient.exe
"C:\Users\Admin\AppData\Local\Temp\AsyncClient.exe"
1⤵
- Checks computer location settings
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
- Suspicious use of WriteProcessMemory
PID:1332

C:\Windows\SysWOW64\cmd.exe
"C:\Windows\System32\cmd.exe" /c schtasks /create /f /sc onlogon /rl highest /tn "exe" /tr '"C:\Users\Admin\AppData\Roaming\exe"' & exit
2⤵
- Suspicious use of WriteProcessMemory
PID:3868

C:\Windows\SysWOW64\schtasks.exe
schtasks /create /f /sc onlogon /rl highest /tn "exe" /tr '"C:\Users\Admin\AppData\Roaming\exe"'
3⤵
- Creates scheduled task(s)
PID:236

C:\Windows\SysWOW64\cmd.exe
C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Local\Temp\tmp8225.tmp.bat""
2⤵
- Modifies registry class
- Suspicious use of WriteProcessMemory
PID:3860

C:\Windows\SysWOW64\timeout.exe
timeout 3
3⤵
- Delays execution with timeout.exe
PID:216

C:\Program Files\Microsoft Office\Root\Office16\WINWORD.EXE
"C:\Program Files\Microsoft Office\Root\Office16\WINWORD.EXE" /n "C:\Users\Admin\Desktop\InstallMerge.odt"
1⤵
- Checks processor information in registry
- Enumerates system info in registry
- Suspicious behavior: AddClipboardFormatListener
- Suspicious use of SetWindowsHookEx
PID:3964

C:\Windows\system32\OpenWith.exe
C:\Windows\system32\OpenWith.exe -Embedding
1⤵
- Modifies registry class
- Suspicious use of SetWindowsHookEx
PID:3188

C:\Windows\System32\WScript.exe
"C:\Windows\System32\WScript.exe" "C:\Users\Admin\Desktop\ConvertToGet.vbs"
1⤵
PID:1572

Network

MITRE ATT&CK Matrix ATT&CK v6

Initial Access

Execution

Scheduled Task

1

T1053

Persistence

Scheduled Task

1

T1053

Privilege Escalation

Scheduled Task

1

T1053

Defense Evasion

Credential Access

Discovery

Query Registry

4

T1012

System Information Discovery

4

T1082

Lateral Movement

Collection

Exfiltration

Command and Control

Impact

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Downloads

C:\Users\Admin\AppData\Local\Temp\tmp8225.tmp.bat
Filesize
143B

MD5
be84c818afec1a028f95ccbfde17363f

SHA1
03d39afe8f53d6eb4953d5c7c2bbbcadf8094617

SHA256
aec087cc4b1c3528756bf078d4be5905ae1cb45c90119be872fb6914500d53e2

SHA512
04bcfc1bd8a88da5e37352235769ce37c48b7eac442bd90550e044d87b81892b8661eec3a85a9a3bd880ddc4d191e8b13fde0f15247414bbdc8d4192a912e170

Download Submit
C:\Users\Admin\AppData\Roaming\exe
Filesize
47KB

MD5
cd56336140a135c2262054ee149c1550

SHA1
8cae4cf270f01d89829c124f8a8883c0844d5443

SHA256
932cb9cc50f478211994f9fff6e753e1ea56877326db099350b8f59b6c236d04

SHA512
785280be15d4bd25245f74c2b5b770e6936655911626d4ed7895ac4ab943c2149e204d5b190c5a6308d2c0fb6075151120f16ecf46e0fa89cd7616b16ac5ba85

Download Submit
memory/1332-133-0x00000000002F0000-0x0000000000302000-memory.dmp

Filesize
72KB

Download
memory/1332-134-0x0000000004D70000-0x0000000004D80000-memory.dmp

Filesize
64KB

Download
memory/1332-135-0x0000000004F80000-0x0000000004FE6000-memory.dmp

Filesize
408KB

Download
memory/1332-136-0x00000000053D0000-0x000000000546C000-memory.dmp

Filesize
624KB

Download
memory/3964-145-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-144-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-143-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-146-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-142-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-148-0x00007FFD22680000-0x00007FFD22690000-memory.dmp

Filesize
64KB

Download
memory/3964-149-0x00007FFD22680000-0x00007FFD22690000-memory.dmp

Filesize
64KB

Download
memory/3964-172-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-173-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-174-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download
memory/3964-175-0x00007FFD24B50000-0x00007FFD24B60000-memory.dmp

Filesize
64KB

Download

Analysis

Sharing

General

Malware Config

Extracted

Signatures

Processes

Network

MITRE ATT&CK Matrix ATT&CK v6

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Downloads