I have a small question. I know that the %x format specifier can be used to read values from the stack in a format string attack.
I found the following code:
%08x%08x%08x%08x
What does the 08 mean? What is it doing exactly? Thanks :)
Break-down:
8
says that you want to show 8 digits0
that you want to prefix with 0
's instead of just blank spacesx
that you want to print in lower-case hexadecimal.Quick example (thanks to Grijesh Chauhan):
#include <stdio.h>
int main() {
int data = 29;
printf("%x\n", data); // just print data
printf("%0x\n", data); // just print data ('0' on its own has no effect)
printf("%8x\n", data); // print in 8 width and pad with blank spaces
printf("%08x\n", data); // print in 8 width and pad with 0's
return 0;
}
Output:
1d
1d
1d
0000001d
Also see http://www.cplusplus.com/reference/cstdio/printf/ for reference.