Analysis

  • max time kernel
    149s
  • max time network
    163s
  • platform
    windows10_x64
  • resource
    win10-en-20210920
  • submitted
    21-10-2021 11:20

General

  • Target

    Enquiry MW886079 ( Flowstar.CO.UK ).exe

  • Size

    901KB

  • MD5

    c396a92cfb2646cde0b781fc5e65bc16

  • SHA1

    337984712bcb8e1ed775008a104013ec171da0e9

  • SHA256

    1bcb5256d3c0ac49ce2b13c2638d2a795f6cdf77591d29cb01d0b3731615470b

  • SHA512

    4f6663135c21f51d63cf635c05f557aede0ac131ca4fbf3375e0a184a1530137ac3607c87b2f4eaf3fd8e5f989c908e9bc0f813f9b57df735b2c20cf03da0f8a

Malware Config

Extracted

Family

remcos

Version

3.3.0 Pro

Botnet

RemoteHost

C2

hadrqlo.ddns.net:4301

Attributes
  • audio_folder

    MicRecords

  • audio_path

    %AppData%

  • audio_record_time

    5

  • connect_delay

    0

  • connect_interval

    1

  • copy_file

    remcos.exe

  • copy_folder

    Remcos

  • delete_file

    false

  • hide_file

    false

  • hide_keylog_file

    false

  • install_flag

    false

  • install_path

    %AppData%

  • keylog_crypt

    true

  • keylog_file

    logs.dat

  • keylog_flag

    false

  • keylog_folder

    remcos

  • keylog_path

    %AppData%

  • mouse_option

    false

  • mutex

    Remcos-27TUGW

  • screenshot_crypt

    false

  • screenshot_flag

    false

  • screenshot_folder

    Screenshots

  • screenshot_path

    %AppData%

  • screenshot_time

    10

  • startup_value

    Remcos

  • take_screenshot_option

    false

  • take_screenshot_time

    5

  • take_screenshot_title

    notepad;solitaire;

Signatures

  • Modifies WinLogon for persistence 2 TTPs 1 IoCs
  • Remcos

    Remcos is a closed-source remote control and surveillance software.

  • Executes dropped EXE 4 IoCs
  • Suspicious use of SetThreadContext 1 IoCs
  • Enumerates physical storage devices 1 TTPs

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

  • Modifies system certificate store 2 TTPs 3 IoCs
  • Suspicious behavior: EnumeratesProcesses 25 IoCs
  • Suspicious behavior: GetForegroundWindowSpam 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 4 IoCs
  • Suspicious use of SetWindowsHookEx 1 IoCs
  • Suspicious use of WriteProcessMemory 27 IoCs

Processes

  • C:\Users\Admin\AppData\Local\Temp\Enquiry MW886079 ( Flowstar.CO.UK ).exe
    "C:\Users\Admin\AppData\Local\Temp\Enquiry MW886079 ( Flowstar.CO.UK ).exe"
    1⤵
    • Suspicious behavior: EnumeratesProcesses
    • Suspicious use of AdjustPrivilegeToken
    • Suspicious use of WriteProcessMemory
    PID:4328
    • C:\Windows\SysWOW64\cmd.exe
      "cmd.exe" /c REG ADD "HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon" /f /v "Shell" /t REG_SZ /d "explorer.exe,C:\Users\Admin\AppData\Roaming\csscr.exe,"
      2⤵
      • Suspicious use of WriteProcessMemory
      PID:4496
      • C:\Windows\SysWOW64\reg.exe
        REG ADD "HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon" /f /v "Shell" /t REG_SZ /d "explorer.exe,C:\Users\Admin\AppData\Roaming\csscr.exe,"
        3⤵
        • Modifies WinLogon for persistence
        PID:496
    • C:\Users\Admin\AppData\Roaming\csscr.exe
      "C:\Users\Admin\AppData\Roaming\csscr.exe"
      2⤵
      • Executes dropped EXE
      • Suspicious use of SetThreadContext
      • Modifies system certificate store
      • Suspicious behavior: EnumeratesProcesses
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of WriteProcessMemory
      PID:500
      • C:\Users\Admin\AppData\Local\Temp\AddInProcess32.exe
        "C:\Users\Admin\AppData\Local\Temp\\AddInProcess32.exe"
        3⤵
        • Executes dropped EXE
        • Suspicious behavior: GetForegroundWindowSpam
        • Suspicious use of SetWindowsHookEx
        PID:1128
      • C:\Users\Admin\AppData\Local\Temp\lssc.exe
        "C:\Users\Admin\AppData\Local\Temp\lssc.exe"
        3⤵
        • Executes dropped EXE
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        • Suspicious use of WriteProcessMemory
        PID:1572
        • C:\Users\Admin\AppData\Local\Temp\lssc.exe
          "C:\Users\Admin\AppData\Local\Temp\lssc.exe"
          4⤵
          • Executes dropped EXE
          • Suspicious behavior: EnumeratesProcesses
          • Suspicious use of AdjustPrivilegeToken
          PID:2156

Network

MITRE ATT&CK Matrix ATT&CK v6

Persistence

Winlogon Helper DLL

1
T1004

Defense Evasion

Modify Registry

2
T1112

Install Root Certificate

1
T1130

Discovery

System Information Discovery

1
T1082

Replay Monitor

Loading Replay Monitor...

Downloads

  • C:\Users\Admin\AppData\Local\Microsoft\CLR_v4.0_32\UsageLogs\lssc.exe.log
    MD5

    e555c48cb712a9597ecb55a60135d1f8

    SHA1

    2081c72d30c34ec3f61f9944545ecdaae11521f7

    SHA256

    815c80df060afa8acf7640ca011735ef77c66666d03901e04a8767827d5da4e9

    SHA512

    32129b5be15217e5400f1e7536270a703d62db60ebb06396b9d74703e6a0dcd2e78f7f42b2019093be1508a9310912f305b88de274a295c9135a4086cd8c8427

  • C:\Users\Admin\AppData\Local\Temp\AddInProcess32.exe
    MD5

    6a673bfc3b67ae9782cb31af2f234c68

    SHA1

    7544e89566d91e84e3cd437b9a073e5f6b56566e

    SHA256

    978a4093058aa2ebf05dc353897d90d950324389879b57741b64160825b5ec0e

    SHA512

    72c302372ce87ceda2a3c70a6005d3f9c112f1641bc7fe6824c718971233e66c07e2996d2785fa358566c38714c25ea812c05c7cfd2f588284849d495fd24f39

  • C:\Users\Admin\AppData\Local\Temp\lssc.exe
    MD5

    0e362e7005823d0bec3719b902ed6d62

    SHA1

    590d860b909804349e0cdc2f1662b37bd62f7463

    SHA256

    2d0dc6216f613ac7551a7e70a798c22aee8eb9819428b1357e2b8c73bef905ad

    SHA512

    518991b68496b3f8545e418cf9b345e0791e09cc20d177b8aa47e0aba447aa55383c64f5bdaca39f2b061a5d08c16f2ad484af8a9f238ca23ab081618fba3ad3

  • C:\Users\Admin\AppData\Local\Temp\lssc.exe
    MD5

    0e362e7005823d0bec3719b902ed6d62

    SHA1

    590d860b909804349e0cdc2f1662b37bd62f7463

    SHA256

    2d0dc6216f613ac7551a7e70a798c22aee8eb9819428b1357e2b8c73bef905ad

    SHA512

    518991b68496b3f8545e418cf9b345e0791e09cc20d177b8aa47e0aba447aa55383c64f5bdaca39f2b061a5d08c16f2ad484af8a9f238ca23ab081618fba3ad3

  • C:\Users\Admin\AppData\Local\Temp\lssc.exe
    MD5

    0e362e7005823d0bec3719b902ed6d62

    SHA1

    590d860b909804349e0cdc2f1662b37bd62f7463

    SHA256

    2d0dc6216f613ac7551a7e70a798c22aee8eb9819428b1357e2b8c73bef905ad

    SHA512

    518991b68496b3f8545e418cf9b345e0791e09cc20d177b8aa47e0aba447aa55383c64f5bdaca39f2b061a5d08c16f2ad484af8a9f238ca23ab081618fba3ad3

  • C:\Users\Admin\AppData\Local\Temp\lssc.txt
    MD5

    4a8fc5310a7d84966f649395425f232d

    SHA1

    ef3d47260d54de5a5d8c2a03158d78b9592c178b

    SHA256

    2f4d30450f1eb1bf9d1c98d2fc67c11b44b3f509b87d05c03b0428728e5ad01a

    SHA512

    b99340075d46567c5ed58989c83836523b0b6d4482a7a531a6590f733c82687c4d13391fb4b890763cfeb3fb41f5c0a1f45e64cf7a86718a98043bd895acbaae

  • C:\Users\Admin\AppData\Local\Temp\lssc.txt
    MD5

    6b0ed42fb02220b903e2af792242b41e

    SHA1

    78972ba6a899d3d8b9dba3b5048582528cf95de5

    SHA256

    5b8e447b227e2d904d100d355ea2732378d054ea752639f05d0ad6c43b5b93ea

    SHA512

    ba2c3232a016a79af401085aa7bfa3dacdc8c78a2a0e483d8fd230bf35a4ade4d665f2a9c9cd4d6dd97c75505e09eae3a766c54e2d0e92cf468132327dd58b92

  • C:\Users\Admin\AppData\Local\Temp\lssc.txt
    MD5

    64304f3a8a4101477eac1bde7983a5cc

    SHA1

    789b9975b9225a74f3765cb884051707dbc45d35

    SHA256

    53a47a0514cb155c6beef7eac36e5c9f7346440bb344e858436d6e47e84cf916

    SHA512

    530e1eccdbac6d27fd5d70a4541d6e1d8332369cb0689d46d9d57b5e4e3aa46ec1c151faba5ae2be65d94361429207aafed262f5b3d7cacf251a9f4eae2c2098

  • C:\Users\Admin\AppData\Roaming\csscr.exe
    MD5

    c396a92cfb2646cde0b781fc5e65bc16

    SHA1

    337984712bcb8e1ed775008a104013ec171da0e9

    SHA256

    1bcb5256d3c0ac49ce2b13c2638d2a795f6cdf77591d29cb01d0b3731615470b

    SHA512

    4f6663135c21f51d63cf635c05f557aede0ac131ca4fbf3375e0a184a1530137ac3607c87b2f4eaf3fd8e5f989c908e9bc0f813f9b57df735b2c20cf03da0f8a

  • C:\Users\Admin\AppData\Roaming\csscr.exe
    MD5

    c396a92cfb2646cde0b781fc5e65bc16

    SHA1

    337984712bcb8e1ed775008a104013ec171da0e9

    SHA256

    1bcb5256d3c0ac49ce2b13c2638d2a795f6cdf77591d29cb01d0b3731615470b

    SHA512

    4f6663135c21f51d63cf635c05f557aede0ac131ca4fbf3375e0a184a1530137ac3607c87b2f4eaf3fd8e5f989c908e9bc0f813f9b57df735b2c20cf03da0f8a

  • memory/496-124-0x0000000000000000-mapping.dmp
  • memory/500-125-0x0000000000000000-mapping.dmp
  • memory/500-134-0x0000000005210000-0x000000000570E000-memory.dmp
    Filesize

    5.0MB

  • memory/500-136-0x0000000007F70000-0x0000000007F7A000-memory.dmp
    Filesize

    40KB

  • memory/500-141-0x0000000005210000-0x000000000570E000-memory.dmp
    Filesize

    5.0MB

  • memory/1128-137-0x0000000000400000-0x0000000000479000-memory.dmp
    Filesize

    484KB

  • memory/1128-140-0x0000000000400000-0x0000000000479000-memory.dmp
    Filesize

    484KB

  • memory/1128-138-0x000000000042FC39-mapping.dmp
  • memory/1572-145-0x0000000000670000-0x0000000000671000-memory.dmp
    Filesize

    4KB

  • memory/1572-142-0x0000000000000000-mapping.dmp
  • memory/2156-149-0x0000000000000000-mapping.dmp
  • memory/4328-122-0x0000000002490000-0x00000000024B4000-memory.dmp
    Filesize

    144KB

  • memory/4328-115-0x0000000000160000-0x0000000000161000-memory.dmp
    Filesize

    4KB

  • memory/4328-121-0x0000000004A30000-0x0000000004AC2000-memory.dmp
    Filesize

    584KB

  • memory/4328-120-0x0000000004A60000-0x0000000004A61000-memory.dmp
    Filesize

    4KB

  • memory/4328-119-0x0000000004B70000-0x0000000004B71000-memory.dmp
    Filesize

    4KB

  • memory/4328-118-0x0000000004AD0000-0x0000000004AD1000-memory.dmp
    Filesize

    4KB

  • memory/4328-117-0x0000000005120000-0x0000000005121000-memory.dmp
    Filesize

    4KB

  • memory/4496-123-0x0000000000000000-mapping.dmp