Black box techniques are the only techniques available for analyzing and testing non-developmental binary executable without first decompiling or disassembling them. Black box tests are not limited in utility to COTS and other executable packages: they are equally valuable for testing compiled custom developed and open source code, enabling the tester to observe the software’s actual behaviors during execution and compare them with behaviors that could only be speculated upon based on extrapolation from indicators in the source code.

Black box testing also allows for examination of the software’s interactions with external entities (environment, users, attackers)—a type of examination that is impossible in white box analyses and tests. One exception is the detection of malicious code. On the other hand, because black box testing can only observe the software as it runs and “from the outside in,” it also provides an incomplete picture.