char *curl_easy_escape(CURL *handle, const char *string, int inlength)
{
  size_t alloc = (inlength?(size_t)inlength:strlen(string))+1;
  char *ns;
  char *testing_ptr = NULL;
  unsigned char in; /* we need to treat the characters unsigned */
  size_t newlen = alloc;
  size_t strindex=0;
  size_t length;
  CURLcode res;

  ns = malloc(alloc);
  if(!ns)
    return NULL;

  length = alloc-1;
  while(length--) {
    in = *string;

    if(Curl_isunreserved(in))
      /* just copy this */
      ns[strindex++]=in;
    else {
      /* encode it */
      newlen += 2; /* the size grows with two, since this'll become a %XX */
      if(newlen > alloc) {
        alloc *= 2;
        testing_ptr = realloc(ns, alloc);
        if(!testing_ptr) {
          free( ns );
          return NULL;
        }
        else {
          ns = testing_ptr;
        }
      }

      res = Curl_convert_to_network(handle, &in, 1);
      if(res) {
        /* Curl_convert_to_network calls failf if unsuccessful */
        free(ns);
        return NULL;
      }

      snprintf(&ns[strindex], 4, "%%%02X", in);

      strindex+=3;
    }
    string++;
  }
  ns[strindex]=0; /* terminate it */
  return ns;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.