The software constructs all or part of a command, data
					structure, or record using externally-influenced input from an upstream
					component, but it does not neutralize or incorrectly neutralizes special
					elements that could modify how it is parsed or interpreted when it is sent to a
					downstream component.Software has certain assumptions about what constitutes data and control
						respectively. It is the lack of verification of these assumptions for
						user-controlled input that leads to injection problems. Injection problems
						encompass a wide variety of issues -- all mitigated in very different ways
						and usually attempted in order to alter the control flow of the process. For
						this reason, the most effective way to discuss these weaknesses is to note
						the distinct features which classify them as injection weaknesses. The most
						important issue to note is that all injection problems share one thing in
						common -- i.e., they allow for the injection of control plane data into the
						user-controlled data plane. This means that the execution of the process may
						be altered by sending code in through legitimate data channels, using no
						other mechanism. While buffer overflows, and many other flaws, involve the
						use of some further issue to gain execution, injection problems need only
						for the data to be parsed. The most classic instantiations of this category
						of weakness are SQL injection and format string vulnerabilities.