Synopsis

User input is used as a divisor without validation.

Enabled by default

Yes

Severity/Certainty

High/Medium

Full description

User input is used as a divisor without first checking that it is within a range. This means that an attacker can send a value that might trigger a division by zero error, for example as part of a denial of service attack.

Coding standards

Code examples

The following code example fails the check and will give a warning:

int main(int argc, char **argv) {
  return 10 / argc;
}

The following code example passes the check and will not give a warning about this issue:

int main(int argc, char **argv) {
  if (argc > 0 && argc < 10)
    return 10 / argc;
  else
    return 1;
}