Buffer Overflow Vulnerability C Code

TurfSixNine — Tue, 28 Feb 2023 11:13:01 +0000

Hi folks,

I have this c code:

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

int ssp(char * str)
{
    char buffer[100];
    strcpy(buffer,str);

    return 1;
}

int main(int argc, char **argv)
{
    char str[400];
    FILE * afile;

    afile = fopen("afile", "r");
           fread(str, sizeof(char), 400, afile);
    ssp(str);

    printf("Returned Properly\n");  

    return 1;
}

The program provided reads the contents of a file called "afile" into a character array called str, which can hold up to 400 characters. It then calls the ssp function and passes str as an argument.

The ssp function copies the contents of the str character array into a local character array called buffer. The strcpy function used to copy the string data does not perform any bounds checking, which can lead to buffer overflow vulnerabilities if the input string is longer than the buffer size.

However, the lack of bounds checking in the strcpy function in the ssp function can potentially lead to buffer overflow vulnerabilities if used in a larger program or in an environment with untrusted input data.

Could anyone please assist with a shellcode at the end of "afile" and then store the shellcode on the stack to run? Please...

DEV Community: TurfSixNine

Buffer Overflow Vulnerability C Code