Analysis

  • max time kernel
    4294179s
  • max time network
    149s
  • platform
    windows7_x64
  • resource
    win7-20220311-en
  • submitted
    21/03/2022, 15:22

General

  • Target
    21344 P.O.rtf
  • Size 11KB
  • Sample220321-sr3x2adeaj
  • SHA256 d55d6e9aa46e97e3900c41584e96d56d23ecc29f8536a5cf3627c7b2e0a563e7
  • MD5 SHA1 SHA512

Malware Config

Extracted

Family
  • asyncrat

Version
  • 0.5.7B

Botnet
  • Default

C2
  • polymoly.info:4199

Mutex
  • AsyncMutex_6SI8OkPnk

Attributes
  • delay

    3

  • install

    false

  • install_file

    siliconsoft.exe

  • install_folder

    %AppData%

aes.plain

Signatures

  • AsyncRat

    AsyncRAT is designed to remotely monitor and control other computers.

  • suricata: ET MALWARE Observed Malicious SSL Cert (AsyncRAT Server)

    suricata: ET MALWARE Observed Malicious SSL Cert (AsyncRAT Server)

  • Async RAT payload 5 IoCs
  • Blocklisted process makes network request 1 IoCs
  • Downloads MZ/PE file
  • Executes dropped EXE 2 IoCs
  • Loads dropped DLL 1 IoCs
  • Suspicious use of SetThreadContext 1 IoCs
  • Drops file in Windows directory 1 IoCs
  • Office loads VBA resources, possible macro or embedded object present
  • Launches Equation Editor 1 TTPs 1 IoCs

    Equation Editor is an old Office component often targeted by exploits such as CVE-2017-11882.

  • Modifies Internet Explorer settings 1 TTPs 31 IoCs
  • Modifies registry class 64 IoCs
  • Suspicious behavior: AddClipboardFormatListener 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of SetWindowsHookEx 2 IoCs
  • Suspicious use of WriteProcessMemory 17 IoCs

Processes

  • C:\Program Files (x86)\Microsoft Office\Office14\WINWORD.EXE
    "C:\Program Files (x86)\Microsoft Office\Office14\WINWORD.EXE" /n "C:\Users\Admin\AppData\Local\Temp\21344 P.O.rtf"
    1⤵
    • Drops file in Windows directory
    • Modifies Internet Explorer settings
    • Modifies registry class
    • Suspicious behavior: AddClipboardFormatListener
    • Suspicious use of SetWindowsHookEx
    • Suspicious use of WriteProcessMemory
    PID:1888
    • C:\Windows\splwow64.exe
      C:\Windows\splwow64.exe 12288
      2⤵
        PID:608
    • C:\Program Files (x86)\Common Files\Microsoft Shared\EQUATION\EQNEDT32.EXE
      "C:\Program Files (x86)\Common Files\Microsoft Shared\EQUATION\EQNEDT32.EXE" -Embedding
      1⤵
      • Blocklisted process makes network request
      • Loads dropped DLL
      • Launches Equation Editor
      • Suspicious use of WriteProcessMemory
      PID:876
      • C:\Users\Admin\AppData\Roaming\aslyd34758.exe
        "C:\Users\Admin\AppData\Roaming\aslyd34758.exe"
        2⤵
        • Executes dropped EXE
        • Suspicious use of SetThreadContext
        • Suspicious use of WriteProcessMemory
        PID:1072
        • C:\Users\Admin\AppData\Roaming\aslyd34758.exe
          "C:\Users\Admin\AppData\Roaming\aslyd34758.exe"
          3⤵
          • Executes dropped EXE
          • Suspicious use of AdjustPrivilegeToken
          PID:1604

    Network

          MITRE ATT&CK Enterprise v6

          Replay Monitor

          Loading Replay Monitor...

          Downloads

          memory/608-68-0x000007FEFB561000-0x000007FEFB563000-memory.dmp

          memory/1072-67-0x0000000000710000-0x0000000000728000-memory.dmp

          memory/1072-66-0x0000000004C80000-0x0000000004C81000-memory.dmp

          memory/1072-70-0x0000000000740000-0x0000000000752000-memory.dmp

          memory/1072-69-0x0000000005980000-0x0000000005A5A000-memory.dmp

          memory/1072-64-0x0000000000240000-0x0000000000324000-memory.dmp

          memory/1072-65-0x000000006AC90000-0x000000006B37E000-memory.dmp

          memory/1604-71-0x0000000000400000-0x0000000000412000-memory.dmp

          memory/1604-79-0x0000000000400000-0x0000000000412000-memory.dmp

          memory/1604-87-0x0000000004BC0000-0x0000000004BC1000-memory.dmp

          memory/1604-85-0x000000006A400000-0x000000006AAEE000-memory.dmp

          memory/1604-82-0x0000000000400000-0x0000000000412000-memory.dmp

          memory/1604-84-0x0000000000400000-0x0000000000412000-memory.dmp

          memory/1604-73-0x0000000000400000-0x0000000000412000-memory.dmp

          memory/1604-75-0x0000000000400000-0x0000000000412000-memory.dmp

          memory/1604-77-0x0000000000400000-0x0000000000412000-memory.dmp

          memory/1888-58-0x0000000074F31000-0x0000000074F33000-memory.dmp

          memory/1888-55-0x000000006FAD1000-0x000000006FAD3000-memory.dmp

          memory/1888-59-0x0000000070ABD000-0x0000000070AC8000-memory.dmp

          memory/1888-54-0x0000000072051000-0x0000000072054000-memory.dmp

          memory/1888-57-0x000000005FFF0000-0x0000000060000000-memory.dmp

          memory/1888-56-0x000000002F420000-0x000000002F57D000-memory.dmp

          memory/1888-88-0x000000005FFF0000-0x0000000060000000-memory.dmp