DbgNexum is a Proof-of-Concept (PoC) tool designed for injecting shellcode into a target process using the Windows Debugging API and Shared Memory techniques. Rather than directly interacting with remote memory, it manipulates the target's execution context to load and run the payload internally. The process begins by attaching to a target application and creating a suspended thread, setting up a Hardware Breakpoint (HWBP) to control execution flow at a predetermined return address. This allows the injector to modify CPU registers dynamically, simulating function calls within the target process. The injection process follows a series of orchestrated stages. Initially, the injector saves the stack pointer and sets a trap flag to manage execution flow. It then allocates memory, prepares data, and ultimately maps the shellcode into the target's address space with execution permissions. The key function calls in this sequence include LocalAlloc, memcpy, memset, OpenFileMappingA, and MapViewOfFile. Each call is forced on the target thread, ensuring that the shellcode is properly loaded and executed. The PoC utilizes XORed shellcode generated by msfvenom, specifically for spawning "calc.exe", but users are encouraged to insert their own payloads. Testing of the technique against Microsoft Defender for Endpoint (MDE) and Elastic security solutions showed no detection, suggesting that this method can effectively bypass certain security measures. The injector’s output provides detailed feedback, including stages of execution and confirmation of successful injection. This approach could be of interest to security researchers and penetration testers looking to understand or demonstrate advanced injection techniques without leveraging traditional methods like WriteProcessMemory or VirtualAllocEx.