CWE-390: Detection of Error Condition Without Action

How it's found

Detection of Error Condition Without Action is typically found by tracing untrusted input from where it enters the system to the point where it is used without the check or neutralization this weakness describes, combining manual code review with dynamic testing.

Vulnerable vs. safe

//We do nothing so we just ignore the error.foo=malloc(sizeof(char)); //the next line checks to see if malloc failedif (foo==NULL) {}

printf("Malloc failed to allocate memory resources");return -1;foo=malloc(sizeof(char)); //the next line checks to see if malloc failedif (foo==NULL) {}

Consequences

• Varies by Context, Unexpected State, Alter Execution Logic: An attacker could utilize an ignored error condition to place the system in an unexpected state that could lead to the execution of unintended logic and could cause other unintended behavior.

Mitigations

• Implementation: Properly handle each exception. This is the recommended solution. Ensure that all exceptions are handled in such a way that you can be sure of the state of your system at any given moment.
• Implementation: If a function returns an error, it is important to either fix the problem and try again, alert the user that an error has happened and let the program continue, or alert the user and close and cleanup the program.
• Testing: Subject the product to extensive testing to discover some of the possible instances of where/how errors or return values are not handled. Consider testing techniques such as ad hoc, equivalence partitioning, robustness and fault tolerance, mutation, and fuzzing.

Where this fits in a TurboPentest engagement

This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.

Frequently asked questions

Related CWEs

• Class weakness
  CWE-755: Improper Handling of Exceptional Conditions