Understanding The Risks

When an application is being created, the Compiler will compile the application source code into several object files made of machine language code. Then the object files are linked together to create the final executable.

In the same manner that the source code of an application is converted into machine code at compilation time, there are tools that can convert a compiled application into assembly language or a higher programming language. These tools are known as dissemblers and de-compilers.

An attacker can use a dissembler or de-compiler to study how a specific application works and what a specific routine does. When the attacker has a good knowledge of the target application, he can modify the compiled application to alter his behavior. For example, the attacker could bypass the routine that checks for the trial period in an application and make it run forever or even worse, cause the application to behave as if it was registered.

Software Protectors
Software protectors where created to keep an attacker from directly inspecting or modifying a compiled application. A software protector is like a shield that keeps an application encrypted and protected against possible attacks. When a protected application is going to be run by the operating system, the software protector will first take control of the CPU and check for possible cracking tools (dissemblers or de-compilers) that may be running on the system. If everything is safe the software protector will proceed to decrypting the protected application and giving it the control of the CPU to be executed as normal.
The advantages of using a Software Protector are:
Protect an application against piracy.
Prevents attackers from studying how an application is implemented.
Will not allow attackers to modify an application to change its behavior .