Analysis

  • max time kernel
    264s
  • max time network
    93s
  • platform
    windows7_x64
  • resource
    win7v20210410
  • submitted
    27-04-2021 14:41

General

  • Target

    thundering-primary.exe

  • Size

    170KB

  • MD5

    f8a2e208360967200b4ac5408aed5556

  • SHA1

    0a4fb1d82225fc7aefe1cc0468022faebbc00a5b

  • SHA256

    b770fb365d1739543878652d8bc885eab35e7ee078635016b7682334e1d6f09d

  • SHA512

    e2cdd4d4094731cab5655f5e87eec3eff7a91a4ad8617ad258a6e11557f59ba117eea7d2d40b325df220b94a44be5f9ffd745ab316f88487ca8cb6697614e21a

Malware Config

Extracted

Path

C:\RyukReadMe.txt

Family

ryuk

Ransom Note
Your network has been penetrated. All files on each host in the network have been encrypted with a strong algorithm. Backups were either encrypted or deleted or backup disks were formatted. Shadow copies also removed, so F8 or any other methods may damage encrypted data but not recover. We exclusively have decryption software for your situation No decryption software is available in the public. DO NOT RESET OR SHUTDOWN - files may be damaged. DO NOT RENAME OR MOVE the encrypted and readme files. DO NOT DELETE readme files. This may lead to the impossibility of recovery of the certain files. To get info (decrypt your files) contact us at [email protected] or [email protected] BTC wallet: 14hVKm7Ft2rxDBFTNkkRC3kGstMGp2A4hk Ryuk No system is safe
Wallets

14hVKm7Ft2rxDBFTNkkRC3kGstMGp2A4hk

Signatures

  • Ryuk

    Ransomware distributed via existing botnets, often Trickbot or Emotet.

  • Deletes shadow copies 2 TTPs

    Ransomware often targets backup files to inhibit system recovery.

  • Modifies extensions of user files 2 IoCs

    Ransomware generally changes the extension on encrypted files.

  • Reads user/profile data of web browsers 2 TTPs

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

  • Adds Run key to start application 2 TTPs 2 IoCs
  • Enumerates connected drives 3 TTPs 18 IoCs

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

  • Drops file in Program Files directory 64 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Interacts with shadow copies 2 TTPs 15 IoCs

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

  • Suspicious behavior: EnumeratesProcesses 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 4 IoCs
  • Suspicious use of UnmapMainImage 2 IoCs
  • Suspicious use of WriteProcessMemory 59 IoCs

Processes

  • C:\Windows\system32\Dwm.exe
    "C:\Windows\system32\Dwm.exe"
    1⤵
    • Modifies extensions of user files
    • Drops file in Program Files directory
    • Suspicious use of UnmapMainImage
    • Suspicious use of WriteProcessMemory
    PID:1212
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /C "C:\users\Public\window.bat"
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:69052
      • C:\Windows\system32\vssadmin.exe
        vssadmin Delete Shadows /all /quiet
        3⤵
        • Interacts with shadow copies
        PID:69080
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=c: /on=c: /maxsize=401MB
        3⤵
        • Interacts with shadow copies
        PID:69068
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=c: /on=c: /maxsize=unbounded
        3⤵
        • Interacts with shadow copies
        PID:69016
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=d: /on=d: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69140
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=d: /on=d: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69164
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=e: /on=e: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69200
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=e: /on=e: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69240
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=f: /on=f: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69284
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=f: /on=f: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69616
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=g: /on=g: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69816
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=g: /on=g: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69872
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=h: /on=h: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69908
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=h: /on=h: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:70316
      • C:\Windows\system32\vssadmin.exe
        vssadmin Delete Shadows /all /quiet
        3⤵
        • Interacts with shadow copies
        PID:1088
  • C:\Windows\system32\taskhost.exe
    "taskhost.exe"
    1⤵
    • Modifies extensions of user files
    • Drops file in Program Files directory
    • Suspicious use of UnmapMainImage
    • Suspicious use of WriteProcessMemory
    PID:1120
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /C "C:\users\Public\window.bat"
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:69680
      • C:\Windows\system32\vssadmin.exe
        vssadmin Delete Shadows /all /quiet
        3⤵
        • Interacts with shadow copies
        PID:69720
  • C:\Users\Admin\AppData\Local\Temp\thundering-primary.exe
    "C:\Users\Admin\AppData\Local\Temp\thundering-primary.exe"
    1⤵
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:1996
    • C:\Windows\System32\cmd.exe
      "C:\Windows\System32\cmd.exe" /C REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run" /v "svchos" /t REG_SZ /d "C:\Users\Admin\AppData\Local\Temp\thundering-primary.exe" /f
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:784
      • C:\Windows\system32\reg.exe
        REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run" /v "svchos" /t REG_SZ /d "C:\Users\Admin\AppData\Local\Temp\thundering-primary.exe" /f
        3⤵
        • Adds Run key to start application
        PID:1696
  • C:\Windows\system32\vssvc.exe
    C:\Windows\system32\vssvc.exe
    1⤵
    • Suspicious use of AdjustPrivilegeToken
    PID:69748
  • C:\Windows\system32\Dwm.exe
    "C:\Windows\system32\Dwm.exe"
    1⤵
      PID:69012

    Network

    MITRE ATT&CK Enterprise v6

    Replay Monitor

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    Downloads

    • memory/1120-63-0x000000013FA60000-0x000000013FDEE000-memory.dmp

      Filesize

      3.6MB

    • memory/1996-60-0x000007FEFC411000-0x000007FEFC413000-memory.dmp

      Filesize

      8KB