I'm sorry, I should have been more direct. No, I meant to say. Using "strcmp" in a typical C program is not a security flaw. It was clear to me you were thinking of "strcat" or "strcpy".
Using strncmp in this situation makes very little sense and is probably more dangerous. The lengths given to strncmp() are inevitably going to be derived from something else that requires a NUL terminator. Meanwhile, strncmp() leaves you open to logic flaws where you compare too few bytes.
Point your string function to a non-null terminated byte buffer for example. At the very least you can crash the app
What's recommended (one of the recommendations) is to use the 'n' functions like strncmp that takes a maximum size.