Resubmissions

11-02-2023 10:59

230211-m3msashg63 10

25-08-2021 10:30

210825-65sp376nnx 10

26-07-2021 12:59

210726-91da1g9v7e 10

Analysis

  • max time kernel
    654s
  • max time network
    678s
  • platform
    windows7_x64
  • resource
    win7v20210410
  • submitted
    25-08-2021 10:30

General

  • Target

    23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.sample.exe

  • Size

    384KB

  • MD5

    5ac0f050f93f86e69026faea1fbb4450

  • SHA1

    9709774fde9ec740ad6fed8ed79903296ca9d571

  • SHA256

    23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2

  • SHA512

    b554487c4e26a85ec5179cdcc1d25b5bc494e8821a8899fbbf868c3cf41f70cc72db107613b3f6655d3ab70f4db94cce2589066bb354b1ed955098d3911b844d

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.

  • Executes dropped EXE 1 IoCs
  • Modifies extensions of user files 2 IoCs

    Ransomware generally changes the extension on encrypted files.

  • Deletes itself 1 IoCs
  • Loads dropped DLL 1 IoCs
  • 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 System32 directory 1 IoCs
  • 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 63 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:69228
      • C:\Windows\system32\vssadmin.exe
        vssadmin Delete Shadows /all /quiet
        3⤵
        • Interacts with shadow copies
        PID:69456
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=c: /on=c: /maxsize=401MB
        3⤵
        • Interacts with shadow copies
        PID:69012
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=c: /on=c: /maxsize=unbounded
        3⤵
        • Interacts with shadow copies
        PID:69120
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=d: /on=d: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69472
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=d: /on=d: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69584
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=e: /on=e: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69628
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=e: /on=e: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69800
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=f: /on=f: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69896
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=f: /on=f: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69912
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=g: /on=g: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:69940
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=g: /on=g: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:70032
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=h: /on=h: /maxsize=401MB
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:70208
      • C:\Windows\system32\vssadmin.exe
        vssadmin resize shadowstorage /for=h: /on=h: /maxsize=unbounded
        3⤵
        • Enumerates connected drives
        • Interacts with shadow copies
        PID:70376
      • C:\Windows\system32\vssadmin.exe
        vssadmin Delete Shadows /all /quiet
        3⤵
        • Interacts with shadow copies
        PID:70432
  • 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⤵
      • Drops file in System32 directory
      • Suspicious use of WriteProcessMemory
      PID:69680
      • C:\Windows\system32\vssadmin.exe
        vssadmin Delete Shadows /all /quiet
        3⤵
        • Interacts with shadow copies
        PID:69716
  • C:\Users\Admin\AppData\Local\Temp\23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.sample.exe
    "C:\Users\Admin\AppData\Local\Temp\23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.sample.exe"
    1⤵
    • Loads dropped DLL
    • Suspicious use of WriteProcessMemory
    PID:2028
    • C:\users\Public\gezKL.exe
      "C:\users\Public\gezKL.exe" C:\Users\Admin\AppData\Local\Temp\23f8aa94ffb3c08a62735fe7fee5799880a8f322ce1d55ec49a13a3f85312db2.sample.exe
      2⤵
      • Executes dropped EXE
      • Deletes itself
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of WriteProcessMemory
      PID:844
      • 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\Public\gezKL.exe" /f
        3⤵
        • Suspicious use of WriteProcessMemory
        PID:1080
        • C:\Windows\system32\reg.exe
          REG ADD "HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run" /v "svchos" /t REG_SZ /d "C:\users\Public\gezKL.exe" /f
          4⤵
          • Adds Run key to start application
          PID:1084
  • C:\Windows\system32\vssvc.exe
    C:\Windows\system32\vssvc.exe
    1⤵
    • Suspicious use of AdjustPrivilegeToken
    PID:69744
  • C:\Windows\system32\Dwm.exe
    "C:\Windows\system32\Dwm.exe"
    1⤵
      PID:69068

    Network

    MITRE ATT&CK Enterprise v6

    Replay Monitor

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    Downloads

    • memory/844-64-0x000007FEFC411000-0x000007FEFC413000-memory.dmp

      Filesize

      8KB

    • memory/1120-67-0x000000013FF00000-0x000000014028E000-memory.dmp

      Filesize

      3.6MB

    • memory/2028-60-0x00000000765F1000-0x00000000765F3000-memory.dmp

      Filesize

      8KB