Taint checking is a security-related software analysis technique.
Taint checking asumes that any variable that can be modified by an external user poses a potential security risk. A taint checking tool compiles a list of all variables which are potentially influenced by outside input. If any of these variables is used to execute dangerous commands (such as direct commands to a SQL database or the host computer operating system), the taint checker warns that the program is using a potentially dangerous tainted variable.
