To make the target process execute the DLL, the kernel driver must force a thread redirection. Common execution vectors include:
A kernel injector is typically a ( .sys ). Once loaded (legitimately via a signed driver or maliciously via a BYOVD attack), it performs these steps:
Security software registers kernel callbacks using functions like ObRegisterCallbacks . This allows an anti-cheat or EDR agent to intercept any attempt to open a handle to a protected process, blocking unauthorized memory allocation or thread creation before it can reach the target application. 3. Memory Scanning and Heuristics
He decided on a more surgical approach: . By using a kernel driver, Elias could intercept a process the moment it was born. He targeted LdrInitializeThunk , the very first function a program runs in user-mode. By queuing a Kernel APC before the process even had a chance to breathe, his DLL would load as part of the "normal" startup flow. The Breach kernel dll injector
In conclusion, kernel DLL injectors are powerful tools used to inject DLLs into the address space of kernel-mode processes. While they have several use cases, including security research, debugging, and digital forensics, they also pose significant risks and challenges. As with any powerful tool, it is essential to use kernel DLL injectors responsibly and with caution to avoid compromising system security and stability.
Because the kernel doesn’t ask permission. It grants it.
Kernel injection shifts the deployment mechanism from user space to kernel space, but the target code still runs in user space. The process generally follows these steps: 1. Gaining Kernel Execution To make the target process execute the DLL,
How to write a basic exploit payload
In real-world malware, this code is obfuscated, packed, and signed with a stolen certificate.
By operating in Ring 0, a malicious injector can systematically unhook or strip the permissions of security software running in user space. Evasion and Detection Trends This allows an anti-cheat or EDR agent to
). By leveraging a kernel driver, the injector can manipulate system structures, bypass user-mode security mechanisms, and inject code directly into privileged or protected processes. Key Differences: User-Mode vs. Kernel-Mode Injection User-Mode Injection Kernel-Mode Injection (Kernel DLL Injector) Ring 3 (User) Ring 0 (Kernel) Methods CreateRemoteThread , SetWindowsHookEx Kernel APIs ( KeStackAttachProcess , ZwMapViewOfSection ) Visibility Easily detected by EDR/Antivirus Highly stealthy, invisible to user-mode apps Targeting Limited by user permissions Can inject into protected system processes How a Kernel DLL Injector Works
The driver allocates virtual memory within the target process using ZwAllocateVirtualMemory to store the shellcode and the DLL path.
Executing the Injection: There are various techniques to trigger the loading of the DLL. One common method is to create a new thread in the target process using an asynchronous procedure call (APC) or by hijacking an existing thread's execution flow. The goal is to force the process to call LoadLibrary, which loads the DLL into its memory space. Techniques and Variations