The article explores a method of injecting code into Windows processes using the Asynchronous Procedure Call mechanism, which allows a payload to be executed inside another process. The author explains how the APC queue works and under what conditions a thread executes the injected code.

Special attention is given to the APC Tandem technique, which uses a chain of calls to improve the reliability and stealth of the injection. As a result, this method can bypass certain security mechanisms and execute code in a less detectable way compared to traditional techniques.

📎 Article: https://medium.com/@s12deff/primitive-process-injection-apc-tandem-1dcec8515c86

APC Tandem Technique in Windows: Stealthy Code Injection via APC