Mhook!

WinAPIOverride is an advanced api monitoring software for 32 and 64 bits processes. You can monitor and/or override any function of a process. This can be done for API functions or executable internal functions.

Deviare In-Process is a code interception engine for Microsoft Windows®. It is a dual license library, GPLv3 and Commercial. The source code is available at GitHub.

How to inject code into another processes address space, and then execute it in the context of this process.; Author: Robert Kuster; Updated: 21 Aug 2003; Section: Threads, Processes & IPC; Chapter: General Programming; Updated: 21 Aug 2003

Microsoft Research Detours v3 Professional is a library for instrumenting arbitrary Win32 functions. Detours intercepts Win32 functions by re-writing the in-memory code for target functions. The Detours package also contains utilities to attach arbitrary DLLs and data segments to any Windows application binary.