Software Engineering Institute

Security vulnerabilities are defects that enable an external party to compromise a system. Our research indicates that improving software quality by reducing the number of errors also reduces the number of vulnerabilities and hence improves software security. Some portion of security vulnerabilities (maybe over half of them) are also quality defects. This report includes security analysis based on data the Software Engineering Institute (SEI) has collected over many years for 100 software development projects. Can quality defect models that predict quality results be applied to security to predict security results? Simple defect models focus on an enumeration of development errors after they have occurred and do not relate directly to operational security vulnerabilities, except when the cause is quality related. This report discusses how a combination of software development and quality techniques can improve software security.