A debugger is a tool that lets an engineer inspect a program while it runs on real hardware. It can pause execution, step through code, read registers and memory, and change values to test how a system behaves. In embedded systems, a debugger is often the best way to see whether a fault is in the software, the hardware, or the surrounding memory path.
In cyber security, debuggers matter for both defense and attack. Defenders use them to reproduce crashes, verify patches, and trace suspicious behavior inside firmware or malware. Attackers may also use debuggers to reverse engineer software, find secrets, or alter control flow. Their limits matter too: on cached systems, the debugger may show stale or misleading values if the tool is not observing the same state as the CPU. That is why secure debugging requires skepticism, cache awareness, and cross-checking against other evidence.