Analysis

  • max time kernel
    102s
  • max time network
    144s
  • platform
    windows7_x64
  • resource
    win7-20230220-en
  • resource tags

    arch:x64arch:x86image:win7-20230220-enlocale:en-usos:windows7-x64system
  • submitted
    24-02-2023 13:27

General

  • Target

    9019.xls

  • Size

    1.1MB

  • MD5

    e43ad32b14cf514db21c3f42b395bf91

  • SHA1

    9a3a51fb5363dcf18279fc0cb32f55e35c438a7c

  • SHA256

    d4e784b7a5cd9c8c2e8838b4b74e5cde203f069e56a4eb9f352e35148f4a30e0

  • SHA512

    2d550d9167bf0f7dab3d2fdca5d08c8a5635b560a981f9aeaed3584b590fdb3ef79ddd03c7516de2c9f8dd9c00de41cc610245edee5555bc2857e9e8db0fbaeb

  • SSDEEP

    24576:3Femy5hspmq1gkOFelnCEezjnk6mgTCTeyszEQrp31XAd6Fv1ib5XXXXXXXXXXXN:VOk+PQhOIOThhzEw3xM6Fu

Malware Config

Extracted

Family

purecrypter

C2

http://www.ugr.leszczynskie.net/galeria/Xcilfp.png

Signatures

  • AgentTesla

    Agent Tesla is a remote access tool (RAT) written in visual basic.

  • PureCrypter

    PureCrypter is a .NET malware loader first seen in early 2021.

  • Blocklisted process makes network request 1 IoCs
  • Downloads MZ/PE file
  • Executes dropped EXE 2 IoCs
  • Loads dropped DLL 1 IoCs
  • Reads data files stored by FTP clients 2 TTPs

    Tries to access configuration files associated with programs like FileZilla.

  • Reads user/profile data of local email clients 2 TTPs

    Email clients store some user data on disk where infostealers will often target it.

  • Reads user/profile data of web browsers 2 TTPs

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

  • Uses the VBS compiler for execution 1 TTPs
  • Accesses Microsoft Outlook profiles 1 TTPs 3 IoCs
  • Adds Run key to start application 2 TTPs 1 IoCs
  • Looks up external IP address via web service 2 IoCs

    Uses a legitimate IP lookup service to find the infected system's external IP.

  • Drops file in System32 directory 1 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.

  • Enumerates system info in registry 2 TTPs 1 IoCs
  • 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 behavior: EnumeratesProcesses 1 IoCs
  • Suspicious use of AdjustPrivilegeToken 3 IoCs
  • Suspicious use of SetWindowsHookEx 4 IoCs
  • Suspicious use of WriteProcessMemory 17 IoCs
  • outlook_office_path 1 IoCs
  • outlook_win_path 1 IoCs

Processes

  • C:\Program Files (x86)\Microsoft Office\Office14\EXCEL.EXE
    "C:\Program Files (x86)\Microsoft Office\Office14\EXCEL.EXE" /dde C:\Users\Admin\AppData\Local\Temp\9019.xls
    1⤵
    • Enumerates system info in registry
    • Modifies Internet Explorer settings
    • Modifies registry class
    • Suspicious behavior: AddClipboardFormatListener
    • Suspicious use of SetWindowsHookEx
    PID:1528
  • 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:268
    • C:\Users\Public\vbc.exe
      "C:\Users\Public\vbc.exe"
      2⤵
      • Executes dropped EXE
      • Suspicious use of SetThreadContext
      • Suspicious use of AdjustPrivilegeToken
      • Suspicious use of WriteProcessMemory
      PID:812
      • C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe
        "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe" -ENC cwB0AGEAcgB0AC0AcwBsAGUAZQBwACAALQBzAGUAYwBvAG4AZABzACAAMgAwAA==
        3⤵
        • Drops file in System32 directory
        • Suspicious behavior: EnumeratesProcesses
        • Suspicious use of AdjustPrivilegeToken
        PID:1744
      • C:\Users\Public\vbc.exe
        C:\Users\Public\vbc.exe
        3⤵
        • Executes dropped EXE
        • Accesses Microsoft Outlook profiles
        • Adds Run key to start application
        • Suspicious use of AdjustPrivilegeToken
        • Suspicious use of SetWindowsHookEx
        • outlook_office_path
        • outlook_win_path
        PID:1788

Network

MITRE ATT&CK Enterprise v6

Replay Monitor

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Downloads

  • C:\Users\Admin\AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.MSO\226E5B87.emf

    Filesize

    34KB

    MD5

    5b29f34fb27ee89c9165a7d4d99d9db8

    SHA1

    05acca26aaed59fa633bbc1c7587806a5960e37c

    SHA256

    3a151e9d05f574ec3cb8d1675d9eebbdc34ff1cd9874541fdeb29cbfb7f3f119

    SHA512

    cb756e3893974b98c093bb1d9acb48348587b1bc125c4581c5fa6f14d59d2005a5a0f4fc02acd975821051c0c997af0bafa0ba06fecebfa8e63326054ce59bf0

  • C:\Users\Admin\AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.MSO\2917D190.emf

    Filesize

    3.2MB

    MD5

    0ac29f307274008930bdd0f9f71ad66e

    SHA1

    fde9130304bbfa17d9e75e4dc05180eec02bc709

    SHA256

    9e3b6eedccb277a72a02d303c096e651dd36573d3a486d6eed2500e0963b6735

    SHA512

    2f437b4f3b0d12cee5ff0ea5f5abe2c70d66d32e2b1178e5ab4195fe05f3cbb367e132bd6142212edaa76288bea8fa23fdaf594e1c9de51e62b3a4acaad2d18b

  • C:\Users\Admin\AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.MSO\8A60562D.emf

    Filesize

    485KB

    MD5

    ee0926f784374bc56c1bbb9bf7c58fc6

    SHA1

    cef843082e435d3db3f361e300b303a868c2d169

    SHA256

    ecd098c54f138c4ca2a75cae732d29ddeae630167548955257e2b07b6f89d229

    SHA512

    5c156691b95dabd95d5d92825626a27c4e88017b67a7a6048a71c0927da2d1aacc4d59b2615f1a19fac3df5edb2c470066b29cadbb8d1784e47c93a8e0bb3744

  • C:\Users\Admin\AppData\Local\Temp\CabAA08.tmp

    Filesize

    61KB

    MD5

    fc4666cbca561e864e7fdf883a9e6661

    SHA1

    2f8d6094c7a34bf12ea0bbf0d51ee9c5bb7939a5

    SHA256

    10f3deb6c452d749a7451b5d065f4c0449737e5ee8a44f4d15844b503141e65b

    SHA512

    c71f54b571e01f247f072be4bbebdf5d8410b67eb79a61e7e0d9853fe857ab9bd12f53e6af3394b935560178107291fc4be351b27deb388eba90ba949633d57d

  • C:\Users\Public\vbc.exe

    Filesize

    25KB

    MD5

    439c8eaf5105f874659e06ecca63e66b

    SHA1

    f264db763cacbcbc6620353097b1cd6367d14afb

    SHA256

    c5f8a57e9e252306e9876a01fbc423420693bf04cf7c33fb0bbf972e34299f21

    SHA512

    2cf9bb028b1d8ca1c321f9a809c6e1d0552992eefc2229661579edeaac8ef0d9926ff1e0a26d8962f6672a45be7bc7b2a86b8331a43a922418569b889853ac5a

  • C:\Users\Public\vbc.exe

    Filesize

    25KB

    MD5

    439c8eaf5105f874659e06ecca63e66b

    SHA1

    f264db763cacbcbc6620353097b1cd6367d14afb

    SHA256

    c5f8a57e9e252306e9876a01fbc423420693bf04cf7c33fb0bbf972e34299f21

    SHA512

    2cf9bb028b1d8ca1c321f9a809c6e1d0552992eefc2229661579edeaac8ef0d9926ff1e0a26d8962f6672a45be7bc7b2a86b8331a43a922418569b889853ac5a

  • C:\Users\Public\vbc.exe

    Filesize

    25KB

    MD5

    439c8eaf5105f874659e06ecca63e66b

    SHA1

    f264db763cacbcbc6620353097b1cd6367d14afb

    SHA256

    c5f8a57e9e252306e9876a01fbc423420693bf04cf7c33fb0bbf972e34299f21

    SHA512

    2cf9bb028b1d8ca1c321f9a809c6e1d0552992eefc2229661579edeaac8ef0d9926ff1e0a26d8962f6672a45be7bc7b2a86b8331a43a922418569b889853ac5a

  • C:\Users\Public\vbc.exe

    Filesize

    25KB

    MD5

    439c8eaf5105f874659e06ecca63e66b

    SHA1

    f264db763cacbcbc6620353097b1cd6367d14afb

    SHA256

    c5f8a57e9e252306e9876a01fbc423420693bf04cf7c33fb0bbf972e34299f21

    SHA512

    2cf9bb028b1d8ca1c321f9a809c6e1d0552992eefc2229661579edeaac8ef0d9926ff1e0a26d8962f6672a45be7bc7b2a86b8331a43a922418569b889853ac5a

  • \Users\Public\vbc.exe

    Filesize

    25KB

    MD5

    439c8eaf5105f874659e06ecca63e66b

    SHA1

    f264db763cacbcbc6620353097b1cd6367d14afb

    SHA256

    c5f8a57e9e252306e9876a01fbc423420693bf04cf7c33fb0bbf972e34299f21

    SHA512

    2cf9bb028b1d8ca1c321f9a809c6e1d0552992eefc2229661579edeaac8ef0d9926ff1e0a26d8962f6672a45be7bc7b2a86b8331a43a922418569b889853ac5a

  • memory/812-79-0x00000000005D0000-0x00000000005EA000-memory.dmp

    Filesize

    104KB

  • memory/812-84-0x00000000049F0000-0x0000000004A30000-memory.dmp

    Filesize

    256KB

  • memory/812-78-0x00000000058A0000-0x0000000005952000-memory.dmp

    Filesize

    712KB

  • memory/812-77-0x00000000049F0000-0x0000000004A30000-memory.dmp

    Filesize

    256KB

  • memory/812-76-0x0000000001330000-0x000000000133C000-memory.dmp

    Filesize

    48KB

  • memory/1528-54-0x000000005FFF0000-0x0000000060000000-memory.dmp

    Filesize

    64KB

  • memory/1528-128-0x000000005FFF0000-0x0000000060000000-memory.dmp

    Filesize

    64KB

  • memory/1744-83-0x0000000002410000-0x0000000002450000-memory.dmp

    Filesize

    256KB

  • memory/1744-85-0x0000000002410000-0x0000000002450000-memory.dmp

    Filesize

    256KB

  • memory/1744-82-0x0000000002410000-0x0000000002450000-memory.dmp

    Filesize

    256KB

  • memory/1788-87-0x0000000000400000-0x0000000000430000-memory.dmp

    Filesize

    192KB

  • memory/1788-94-0x0000000000400000-0x0000000000430000-memory.dmp

    Filesize

    192KB

  • memory/1788-96-0x0000000000400000-0x0000000000430000-memory.dmp

    Filesize

    192KB

  • memory/1788-97-0x0000000001200000-0x0000000001240000-memory.dmp

    Filesize

    256KB

  • memory/1788-91-0x0000000000400000-0x0000000000430000-memory.dmp

    Filesize

    192KB

  • memory/1788-122-0x0000000001200000-0x0000000001240000-memory.dmp

    Filesize

    256KB

  • memory/1788-90-0x000000007EFDE000-0x000000007EFDF000-memory.dmp

    Filesize

    4KB

  • memory/1788-89-0x0000000000400000-0x0000000000430000-memory.dmp

    Filesize

    192KB

  • memory/1788-88-0x0000000000400000-0x0000000000430000-memory.dmp

    Filesize

    192KB

  • memory/1788-86-0x0000000000400000-0x0000000000430000-memory.dmp

    Filesize

    192KB