| Feature | Standard EXE | Shellcode | | :--- | :--- | :--- | | | Expects main or WinMain to be called by the loader | Raw bytes; execution starts at the first byte | | Memory Layout | Relies on Windows loader to map sections ( .text , .data , .rdata ) at proper virtual addresses | Position-independent; must work wherever injected | | Imports | Uses Import Address Table (IAT) resolved by loader | Must resolve APIs manually at runtime | | Base Address | Assumes a preferred base (e.g., 0x400000 ); relocation required if occupied | Cannot assume any fixed address | | Initialization | CRT initialization, TLS callbacks, and global constructors | No runtime environment; must self-initialize |
But how does one transform a Portable Executable (PE) into a raw block of position-independent code? This article explores the theory, methods, tooling, and limitations of this conversion. Before diving into conversion, we must understand why an .exe cannot simply be renamed or copied into a shellcode buffer. convert exe to shellcode
Writing a multi-stage beacon from scratch in assembly is impractical. Enter the technique of . This process allows attackers to leverage fully-featured compiled binaries (e.g., a custom messenger.exe or beacon.exe ) and inject them directly into memory without touching the disk. | Feature | Standard EXE | Shellcode |
You must understand the limitations: the target process architecture must match, the EXE must be relocatable or compiled with PIC, and modern EDRs can still catch you via behavioral or memory signatures. Writing a multi-stage beacon from scratch in assembly
