alpine 3.7
format weakness #29


Weakness Breakdown


A format string exploit occurs when the data of an input string is evaluated as a command by the program. This class of attacks is very similar to buffer overflows since an attacker could execute code, read the stack or cause new behaviors that compromise security. Learn more about format string attacks on OWASP attack index.

Warning code(s):

If format strings can be influenced by an attacker, they can be exploited.

File Name:



The highlighted line of code below is the trigger point of this particular Alpine 3.7 format weakness.

 #include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <stddef.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>       /* for time() and time_t */
#include <ctype.h>
#include <netdb.h>
#include <signal.h>
#include "dpiutil.h"
#include "../dpip/dpip.h"

 * Debugging macros
#define _MSG(...)
#define MSG(...)  printf("[cookies dpi]: " __VA_ARGS__)

 * a_List_add()
 * Make sure there's space for 'num_items' items within the list
 * (First, allocate an 'alloc_step' sized chunk, after that, double the
 *  list size --to make it faster)
#define a_List_add(list,num_items,alloc_step) \
   if (!list) { \
      list = dMalloc(alloc_step * sizeof((*list))); \
   } \
   if (num_items >= alloc_step){ \
      while ( num_items >= alloc_step ) \
         alloc_step <<= 1; \
      list = dRealloc(list, alloc_step * sizeof((*list))); \

/* The maximum length of a line in the cookie file */
#define LINE_MAXLEN 4096

#define MAX_TOTAL_COOKIES 1200

typedef enum { 

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