Error Conditions, Return Values, Status Codes

This category includes weaknesses that occur if a function does not generate the correct return/status code, or if the application does not handle all possible return/status codes that could be generated by a function. This type of problem is most often found in conditions that are rarely encountered during the normal operation of the product. Presumably, most bugs related to common conditions are found and eliminated during development and testing. In some cases, the attacker can directly control or influence the environment to trigger the rare conditions.