Analysis

  • max time kernel
    135s
  • max time network
    124s
  • platform
    windows7_x64
  • resource
    win7-20241010-en
  • resource tags

    arch:x64arch:x86image:win7-20241010-enlocale:en-usos:windows7-x64system
  • submitted
    15-12-2024 12:48

General

  • Target

    FnClient.exe

  • Size

    1.6MB

  • MD5

    794aff3545f0ea50584adc40dd2f0896

  • SHA1

    6130d56bf9ba1cbe320f0b24141b0c9491584d3f

  • SHA256

    18888fdc50df5f29587b1c83cb5a217d4837f5fb31b74b010e2337de4b5da988

  • SHA512

    d7d9ca25f7535f10232b715ef5662f7316c512dc7da1036d3a31e77922fcaa30e5066fcf7142c743147e2d9aebdbf778be0390512a6f397c692118d7f11f1239

  • SSDEEP

    12288:ofUX9SOQjN9wr5jpvkP3bap3WUkv9wO4ngeA4EoELzXKlfGba5hvMNGcxzY5Sqax:hAbIfIgJGRg85sPDr/VkJ4UB

Malware Config

Signatures

  • Chaos

    Ransomware family first seen in June 2021.

  • Chaos Ransomware 3 IoCs
  • Chaos family
  • Deletes shadow copies 3 TTPs

    Ransomware often targets backup files to inhibit system recovery.

  • Modifies boot configuration data using bcdedit 1 TTPs 2 IoCs
  • Deletes backup catalog 3 TTPs 1 IoCs

    Uses wbadmin.exe to inhibit system recovery.

  • Drops startup file 3 IoCs
  • Executes dropped EXE 1 IoCs
  • Reads user/profile data of web browsers 3 TTPs

    Infostealers often target stored browser data, which can include saved credentials etc.

  • Drops desktop.ini file(s) 34 IoCs
  • Sets desktop wallpaper using registry 2 TTPs 2 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Interacts with shadow copies 3 TTPs 1 IoCs

    Shadow copies are often targeted by ransomware to inhibit system recovery.

  • Modifies registry class 6 IoCs
  • Opens file in notepad (likely ransom note) 1 IoCs
  • Suspicious behavior: AddClipboardFormatListener 2 IoCs
  • Suspicious behavior: EnumeratesProcesses 7 IoCs
  • Suspicious behavior: GetForegroundWindowSpam 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 48 IoCs
  • Suspicious use of FindShellTrayWindow 5 IoCs
  • Suspicious use of SendNotifyMessage 3 IoCs
  • Suspicious use of SetWindowsHookEx 1 IoCs
  • Suspicious use of WriteProcessMemory 30 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.

  • Uses Volume Shadow Copy service COM API

    The Volume Shadow Copy service is used to manage backups/snapshots.

Processes

  • C:\Users\Admin\AppData\Local\Temp\FnClient.exe
    "C:\Users\Admin\AppData\Local\Temp\FnClient.exe"
    1⤵
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:1740
    • C:\Users\Admin\AppData\Roaming\svchost.exe
      "C:\Users\Admin\AppData\Roaming\svchost.exe"
      2⤵
      • Drops startup file
      • Executes dropped EXE
      • Drops desktop.ini file(s)
      • Sets desktop wallpaper using registry
      • Suspicious behavior: AddClipboardFormatListener
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of WriteProcessMemory
      PID:2620
      • C:\Windows\System32\cmd.exe
        "C:\Windows\System32\cmd.exe" /C vssadmin delete shadows /all /quiet & wmic shadowcopy delete
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:1764
        • C:\Windows\system32\vssadmin.exe
          vssadmin delete shadows /all /quiet
          4⤵
          • Interacts with shadow copies
          PID:2976
        • C:\Windows\System32\Wbem\WMIC.exe
          wmic shadowcopy delete
          4⤵
          • Suspicious use of AdjustPrivilegeToken
          PID:992
      • C:\Windows\System32\cmd.exe
        "C:\Windows\System32\cmd.exe" /C bcdedit /set {default} bootstatuspolicy ignoreallfailures & bcdedit /set {default} recoveryenabled no
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:2088
        • C:\Windows\system32\bcdedit.exe
          bcdedit /set {default} bootstatuspolicy ignoreallfailures
          4⤵
          • Modifies boot configuration data using bcdedit
          PID:864
        • C:\Windows\system32\bcdedit.exe
          bcdedit /set {default} recoveryenabled no
          4⤵
          • Modifies boot configuration data using bcdedit
          PID:1192
      • C:\Windows\System32\cmd.exe
        "C:\Windows\System32\cmd.exe" /C wbadmin delete catalog -quiet
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:1884
        • C:\Windows\system32\wbadmin.exe
          wbadmin delete catalog -quiet
          4⤵
          • Deletes backup catalog
          PID:1556
      • C:\Windows\system32\NOTEPAD.EXE
        "C:\Windows\system32\NOTEPAD.EXE" C:\Users\Admin\AppData\Roaming\read_it.txt
        3⤵
        • Opens file in notepad (likely ransom note)
        • Suspicious use of FindShellTrayWindow
        PID:2112
  • C:\Windows\system32\rundll32.exe
    "C:\Windows\system32\rundll32.exe" C:\Windows\system32\shell32.dll,OpenAs_RunDLL C:\Users\Admin\Desktop\UnlockResolve.vbs.8kp7
    1⤵
    • Modifies registry class
    PID:2892
  • C:\Windows\system32\vssvc.exe
    C:\Windows\system32\vssvc.exe
    1⤵
    • Suspicious use of AdjustPrivilegeToken
    PID:1312
  • C:\Windows\system32\wbengine.exe
    "C:\Windows\system32\wbengine.exe"
    1⤵
    • Suspicious use of AdjustPrivilegeToken
    PID:2540
  • C:\Windows\System32\vdsldr.exe
    C:\Windows\System32\vdsldr.exe -Embedding
    1⤵
      PID:2564
    • C:\Windows\System32\vds.exe
      C:\Windows\System32\vds.exe
      1⤵
        PID:2520
      • C:\Windows\system32\rundll32.exe
        "C:\Windows\system32\rundll32.exe" C:\Windows\system32\shell32.dll,OpenAs_RunDLL C:\Users\Admin\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Internet Explorer.lnk.e4ut
        1⤵
        • Modifies registry class
        PID:1576
      • C:\Windows\system32\rundll32.exe
        "C:\Windows\system32\rundll32.exe" C:\Windows\system32\shell32.dll,OpenAs_RunDLL C:\Users\Admin\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Internet Explorer.lnk.e4ut
        1⤵
        • Modifies registry class
        PID:2240
      • C:\Windows\system32\rundll32.exe
        "C:\Windows\system32\rundll32.exe" C:\Windows\system32\shell32.dll,OpenAs_RunDLL C:\Users\Admin\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Windows Explorer.lnk.a36j
        1⤵
        • Modifies registry class
        PID:2324
      • C:\Windows\system32\rundll32.exe
        "C:\Windows\system32\rundll32.exe" C:\Windows\system32\shell32.dll,OpenAs_RunDLL C:\Users\Admin\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Windows Media Player.lnk.hjd6
        1⤵
        • Modifies registry class
        PID:2076
      • C:\Windows\system32\rundll32.exe
        "C:\Windows\system32\rundll32.exe" C:\Windows\system32\shell32.dll,OpenAs_RunDLL C:\Users\Admin\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Google Chrome.lnk.ihsd
        1⤵
        • Modifies registry class
        PID:1384
      • C:\Windows\system32\rundll32.exe
        "C:\Windows\system32\rundll32.exe" shell32.dll,Options_RunDLL 7
        1⤵
          PID:2228
        • C:\Program Files\VideoLAN\VLC\vlc.exe
          "C:\Program Files\VideoLAN\VLC\vlc.exe" --started-from-file "C:\Users\Admin\Desktop\LockUpdate.TS"
          1⤵
          • Suspicious behavior: AddClipboardFormatListener
          • Suspicious behavior: GetForegroundWindowSpam
          • Suspicious use of FindShellTrayWindow
          • Suspicious use of SendNotifyMessage
          • Suspicious use of SetWindowsHookEx
          PID:2884

        Network

        MITRE ATT&CK Enterprise v15

        Replay Monitor

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        Downloads

        • C:\Users\Admin\AppData\Roaming\svchost.exe

          Filesize

          1.6MB

          MD5

          794aff3545f0ea50584adc40dd2f0896

          SHA1

          6130d56bf9ba1cbe320f0b24141b0c9491584d3f

          SHA256

          18888fdc50df5f29587b1c83cb5a217d4837f5fb31b74b010e2337de4b5da988

          SHA512

          d7d9ca25f7535f10232b715ef5662f7316c512dc7da1036d3a31e77922fcaa30e5066fcf7142c743147e2d9aebdbf778be0390512a6f397c692118d7f11f1239

        • C:\Users\Admin\Documents\read_it.txt

          Filesize

          785B

          MD5

          d1bda10d6a8783f5d72eb4f2ac35abf8

          SHA1

          b9ae3b5f6c9082d66df9cfb07565a65820b2699a

          SHA256

          6a2196d66cd38e04d7699c2899dc60260e77c72faf009e8d6f2ba02b98df48af

          SHA512

          b860296368b255973c9aeaee652bfc3a3691aaacb4ed38623dc3f3453343d08de7a2eda44621684e35ef31a424fda6719c652a6fb378258764cacae53cb63a2d

        • memory/1740-1-0x00000000013C0000-0x0000000001556000-memory.dmp

          Filesize

          1.6MB

        • memory/1740-0-0x000007FEF5DD3000-0x000007FEF5DD4000-memory.dmp

          Filesize

          4KB

        • memory/2620-7-0x0000000000AE0000-0x0000000000C76000-memory.dmp

          Filesize

          1.6MB

        • memory/2620-21-0x000007FEF5DD0000-0x000007FEF67BC000-memory.dmp

          Filesize

          9.9MB

        • memory/2620-28-0x000007FEF5DD0000-0x000007FEF67BC000-memory.dmp

          Filesize

          9.9MB

        • memory/2620-437-0x000007FEF5DD0000-0x000007FEF67BC000-memory.dmp

          Filesize

          9.9MB

        • memory/2620-463-0x000007FEF5DD0000-0x000007FEF67BC000-memory.dmp

          Filesize

          9.9MB

        • memory/2884-503-0x000000013F620000-0x000000013F718000-memory.dmp

          Filesize

          992KB

        • memory/2884-504-0x000007FEFB450000-0x000007FEFB484000-memory.dmp

          Filesize

          208KB

        • memory/2884-505-0x000007FEED3B0000-0x000007FEED666000-memory.dmp

          Filesize

          2.7MB

        • memory/2884-506-0x000007FEEC300000-0x000007FEED3B0000-memory.dmp

          Filesize

          16.7MB