Analysis

  • max time kernel
    94s
  • max time network
    96s
  • platform
    windows10-2004_x64
  • resource
    win10v2004-20220812-en
  • resource tags

    arch:x64arch:x86image:win10v2004-20220812-enlocale:en-usos:windows10-2004-x64system
  • submitted
    23/01/2023, 22:30

General

  • Target

    http://ammyy.com/en

Malware Config

Signatures

  • Ammyy Admin

    Remote admin tool with various capabilities.

  • AmmyyAdmin payload 4 IoCs
  • FlawedAmmyy RAT

    Remote-access trojan based on leaked code for the Ammyy remote admin software.

  • Blocklisted process makes network request 1 IoCs
  • Downloads MZ/PE file
  • Executes dropped EXE 3 IoCs
  • Checks computer location settings 2 TTPs 1 IoCs

    Looks up country code configured in the registry, likely geofence.

  • Loads dropped DLL 1 IoCs
  • Writes to the Master Boot Record (MBR) 1 TTPs 2 IoCs

    Bootkits write to the MBR to gain persistence at a level below the operating system.

  • Drops file in System32 directory 11 IoCs
  • Program crash 1 IoCs
  • Modifies Internet Explorer Phishing Filter 1 TTPs 2 IoCs
  • Modifies Internet Explorer settings 1 TTPs 41 IoCs
  • Modifies data under HKEY_USERS 11 IoCs
  • Suspicious behavior: EnumeratesProcesses 2 IoCs
  • Suspicious behavior: GetForegroundWindowSpam 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 1 IoCs
  • Suspicious use of FindShellTrayWindow 4 IoCs
  • Suspicious use of SendNotifyMessage 1 IoCs
  • Suspicious use of SetWindowsHookEx 6 IoCs
  • Suspicious use of WriteProcessMemory 11 IoCs

Processes

  • C:\Program Files\Internet Explorer\iexplore.exe
    "C:\Program Files\Internet Explorer\iexplore.exe" http://ammyy.com/en
    1⤵
    • Modifies Internet Explorer Phishing Filter
    • Modifies Internet Explorer settings
    • Suspicious use of FindShellTrayWindow
    • Suspicious use of SetWindowsHookEx
    • Suspicious use of WriteProcessMemory
    PID:2828
    • C:\Program Files (x86)\Internet Explorer\IEXPLORE.EXE
      "C:\Program Files (x86)\Internet Explorer\IEXPLORE.EXE" SCODEF:2828 CREDAT:17410 /prefetch:2
      2⤵
      • Modifies Internet Explorer settings
      • Suspicious use of SetWindowsHookEx
      PID:4920
    • C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe
      "C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe"
      2⤵
      • Executes dropped EXE
      • Writes to the Master Boot Record (MBR)
      PID:2476
  • C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe
    "C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe" -service -lunch
    1⤵
    • Executes dropped EXE
    • Suspicious use of WriteProcessMemory
    PID:1832
    • C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe
      "C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe"
      2⤵
      • Executes dropped EXE
      • Checks computer location settings
      • Writes to the Master Boot Record (MBR)
      • Drops file in System32 directory
      • Modifies data under HKEY_USERS
      • Suspicious behavior: GetForegroundWindowSpam
      • Suspicious use of FindShellTrayWindow
      • Suspicious use of SendNotifyMessage
      • Suspicious use of WriteProcessMemory
      PID:1692
      • C:\Windows\SYSTEM32\rundll32.exe
        rundll32.exe "C:\ProgramData\AMMYY\aa_nts.dll",run
        3⤵
        • Blocklisted process makes network request
        • Loads dropped DLL
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        PID:3952
  • C:\Windows\system32\WerFault.exe
    C:\Windows\system32\WerFault.exe -pss -s 476 -p 2644 -ip 2644
    1⤵
      PID:2144
    • C:\Windows\system32\WerFault.exe
      C:\Windows\system32\WerFault.exe -u -p 2644 -s 2480
      1⤵
      • Program crash
      PID:1604

    Network

    MITRE ATT&CK Enterprise v6

    Replay Monitor

    Loading Replay Monitor...

    Downloads

    • C:\ProgramData\AMMYY\aa_nts.dll

      Filesize

      902KB

      MD5

      480a66902e6e7cdafaa6711e8697ff8c

      SHA1

      6ac730962e7c1dba9e2ecc5733a506544f3c8d11

      SHA256

      7eaaaa6010bbcd6bb8c9ad08d4b0966c7aedc9b2ac24758f170012ac36e508b5

      SHA512

      7d010cd47b7d1adf66f9c97afc6c3805997aa5c7cc6ff13eddee81f24cf2b95a3fe375ec5b3d6185c0bc8840b4ad91ae143c73a39af26391cc182ab6a1793ba5

    • C:\ProgramData\AMMYY\aa_nts.dll

      Filesize

      902KB

      MD5

      480a66902e6e7cdafaa6711e8697ff8c

      SHA1

      6ac730962e7c1dba9e2ecc5733a506544f3c8d11

      SHA256

      7eaaaa6010bbcd6bb8c9ad08d4b0966c7aedc9b2ac24758f170012ac36e508b5

      SHA512

      7d010cd47b7d1adf66f9c97afc6c3805997aa5c7cc6ff13eddee81f24cf2b95a3fe375ec5b3d6185c0bc8840b4ad91ae143c73a39af26391cc182ab6a1793ba5

    • C:\ProgramData\AMMYY\aa_nts.msg

      Filesize

      46B

      MD5

      3f05819f995b4dafa1b5d55ce8d1f411

      SHA1

      404449b79a16bfc4f64f2fd55cd73d5d27a85d71

      SHA256

      7e0bf0cbd06a087500a9c3b50254df3a8a2c2980921ab6a62ab1121941c80fc0

      SHA512

      34abb7df8b3a68e1649ff0d2762576a4d4e65da548e74b1aa65c2b82c1b89f90d053ecddac67c614ca6084dc5b2cb552949250fb70f49b536f1bcb0057717026

    • C:\ProgramData\AMMYY\settings3.bin

      Filesize

      327B

      MD5

      c26022154f9e5054fdb90b681c84f0f9

      SHA1

      ff3527b6fed3d45f1014684c08b4a506110a1c80

      SHA256

      cf9a4f8d510251b3d28604dc81f862d047adf3c8faafbbac35f75c8880279bf9

      SHA512

      0964874bf2d548afdaa701fc6732360574bf2f8c3a3bfd369f793c3db7499c11cda304f3ff43760fe8e0893ec7e9f6c637fd04ea8f13e63ad7af476f725aad79

    • C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\Content\7423F88C7F265F0DEFC08EA88C3BDE45_AA1E8580D4EBC816148CE81268683776

      Filesize

      471B

      MD5

      7e11ac71f55b340cc49bc0f857a36273

      SHA1

      797009780b7ce9c1fa4359a307e3f12e78ef2691

      SHA256

      b710fcbb8dfc6383be4551b6bfbc3bd513e20f5e40959d74f38100aa17debdd2

      SHA512

      84dfab72afef191260dd8cf5d553a641bc1043bc9bdd387a0f6c7663fb9935f9b333823c79da45b8d3af59f7408d10314297fbb1e2ae98f497af4e322795b828

    • C:\Users\Admin\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\7423F88C7F265F0DEFC08EA88C3BDE45_AA1E8580D4EBC816148CE81268683776

      Filesize

      404B

      MD5

      45c01dc32fcaaf7649804d3f0199f28f

      SHA1

      8ac38bcf3ea234f3535ab149c32715c1448624b0

      SHA256

      ba396551e612237ecd5f74bc0def76493a53279d7bea91c0554f3ede74430db9

      SHA512

      e7fb25a2596291aef91e68780b7cfee991ebd6e87814c4b7d5467424122cc20e627d2836408fe591b8a487fa7f6647fd081247709ed51a46b5733a818f98e17c

    • C:\Users\Admin\AppData\Local\Microsoft\Internet Explorer\imagestore\ru1r3yf\imagestore.dat

      Filesize

      3KB

      MD5

      23c36c35e9cf6480d25557c9a6c1c1ce

      SHA1

      f72b9768b844a9790c9c82c5248b654350f25307

      SHA256

      34b38dc7f75bc1845e81b91d62252ef22a76a5f8c3f615fc7f354ab83dbb5f99

      SHA512

      1d58012a7f5b441b4a3fad61a368d7cc82253271cb2983694c2701963440bc628b9ca08e774a8ffa9a04242bb5071ab59ae3b6bac4901b355ba75cfd1abaacdb

    • C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe

      Filesize

      798KB

      MD5

      90aadf2247149996ae443e2c82af3730

      SHA1

      050b7eba825412b24e3f02d76d7da5ae97e10502

      SHA256

      ee573647477339784dcef81024de1be1762833a20e5cc2b89a93e47d05b86b6a

      SHA512

      eec32bb82b230dd309c29712e72d4469250e651449e127479d178eddbafd5a46ec8048a753bc2c1a0fdf1dc3ed72a9453ca66fb49cbf0f95a12704e5427182be

    • C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe

      Filesize

      798KB

      MD5

      90aadf2247149996ae443e2c82af3730

      SHA1

      050b7eba825412b24e3f02d76d7da5ae97e10502

      SHA256

      ee573647477339784dcef81024de1be1762833a20e5cc2b89a93e47d05b86b6a

      SHA512

      eec32bb82b230dd309c29712e72d4469250e651449e127479d178eddbafd5a46ec8048a753bc2c1a0fdf1dc3ed72a9453ca66fb49cbf0f95a12704e5427182be

    • C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe

      Filesize

      798KB

      MD5

      90aadf2247149996ae443e2c82af3730

      SHA1

      050b7eba825412b24e3f02d76d7da5ae97e10502

      SHA256

      ee573647477339784dcef81024de1be1762833a20e5cc2b89a93e47d05b86b6a

      SHA512

      eec32bb82b230dd309c29712e72d4469250e651449e127479d178eddbafd5a46ec8048a753bc2c1a0fdf1dc3ed72a9453ca66fb49cbf0f95a12704e5427182be

    • C:\Users\Admin\AppData\Local\Microsoft\Windows\INetCache\IE\G9LDH5FK\AA_v3.exe.01j18rb.partial

      Filesize

      798KB

      MD5

      90aadf2247149996ae443e2c82af3730

      SHA1

      050b7eba825412b24e3f02d76d7da5ae97e10502

      SHA256

      ee573647477339784dcef81024de1be1762833a20e5cc2b89a93e47d05b86b6a

      SHA512

      eec32bb82b230dd309c29712e72d4469250e651449e127479d178eddbafd5a46ec8048a753bc2c1a0fdf1dc3ed72a9453ca66fb49cbf0f95a12704e5427182be