Synopsis

A potentially unsafe library function is used.

Enabled by default

No

Severity/Certainty

Medium/Medium

Full description

A potentially unsafe library function is used, for which there is a safer alternative. This library function might create vulnerabilities like possible buffer overflow, because it does not check the size of a string before copying it into memory. The problem is that strcpy() and gets() functions are used. strncpy() should be used instead of strcpy(), and fgets() instead of gets(), because they include an additional argument in which the input's maximum allowed length is specified.

Coding standards

Code examples

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

#include <stdio.h>

void example(char* buf1) {
  scanf("%s", buf1);
}

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

#include <stdio.h>

void example(char* buf1, char* buf2) {
  strncpy(buf1, buf2, 5);
}