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A buffer overflow is the result of stuffing more data into a buffer than
it can handle.
In the example, the program has a function with a typical buffer overflow coding error.
Dangerous functions for stack overflow (don't check the string boundaries):
strcat(), strcpy(), sprintf(), vsprintf(), gets(), scanf().
To exploit such flaw, an attacker would need to give a specially crafted
encoded input. It can be done localy by using a rootkit or over a network
by sending a packet with improperly advertised lengths.
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#include <string.h>
void function(char *str) {
char buffer[16];
strcpy(buffer,str);
}
int main() {
char large_string[256];
int i;
for( i = 0; i < 255; i++)
large_string[i] = 'A';
function(large_string);
}
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