Vmprotect Unpacker: X64dbg

analyze_memory: log "[+] VirtualProtect called - analyzing memory region" dump esp // Examine stack for protection changes

def restore_iat(self): """Rebuild Import Address Table""" # VMProtect redirects IAT to its own handlers # Need to trace API calls and restore original addresses pass

// Step 4: Look for typical VMProtect patterns findpattern: find base_address, #558BEC83EC??53# // Common prologue pattern cmp $result, 0 je continue_search log "[+] Found potential VM handler at: {@result}"

// When VirtualProtect hits, check for memory changes check_oep: cmp eip, VirtualProtect je analyze_memory jmp continue_execution vmprotect unpacker x64dbg

// Step 7: Locate OEP after unpacking bp VirtualProtect erun // Execute until VirtualProtect is hit

// Step 8: OEP finder after unpacking completes find_oep: // Look for typical entry point patterns find base_address, #6A??68????????E8????????# // Push pattern cmp $result, 0 je not_found log "[!] Potential OEP candidate at: {@result}" oep_address = $result bp oep_address

// Step 10: Log all API calls for tracing logapi: log "[API] {@eip} - {@eax}" stepover jmp logapi Setting Breakpoints bp kernel32.VirtualAlloc bp kernel32.VirtualProtect bp ntdll.NtProtectVirtualMemory bp kernel32.GetProcAddress Memory Scanning // Search for VM entry point s 401000 L? E9???????? // JMP near pattern s 401000 L? 0F85???????? // JNE near pattern Tracing Execution // Step through virtualized code traceinto 10000 // Trace 10000 instructions tracetoggle Manual Unpacking Workflow # Python conceptual framework (not a working unpacker) class VMProtectAnalyzer: def init (self, target_path): self.target = target_path self.vm_handlers = [] self.oep = None # Standard prologue b'\xFF\x25'

def find_vm_entry(self): """Locate virtual machine entry point""" # VM handlers often have characteristic instruction sequences patterns = [ b'\x55\x8B\xEC\x83\xEC', # Standard prologue b'\xFF\x25', # Indirect JMP b'\xE8\x00\x00\x00\x00' # CALL $+5 ] return self.scan_memory(patterns)

// Step 3: Trace to find original entry point log "[*] Tracing to find Original Entry Point..." run

// Step 2: Set hardware breakpoints on common VM entry points bp mod.main() bp VirtualProtect bp VirtualAlloc bp GetProcAddress #6A??68????????E8????????# // Push pattern cmp $result

def extract_unpacked(self): """Dump unpacked sections to memory""" # After unpacking, dump memory regions import struct # Map memory sections and write to file pass

// Step 1: Identify target sections msg "Starting VMProtect analysis..." base_address = mod.base() section_start = base_address + 0x1000