22019, 1/1101 ȸ¿ø°¡ÀÔ  ·Î±×ÀΠ 
   benkim
   level5 race condition

http://www.hackerschool.org/HS_Boards/zboard.php?AllArticle=true&no=30930 [º¹»ç]


Á¦°¡ level5¸¦ ¸ô¶ó¼­ ³×À̹ö¿¡ °Ë»ö Çß½À´Ï´Ù ±×·±µ¥ Á¦°¡ ³×À̹ö ºí·Î±×¿¡ ³ª¿ÍÀִ°Ŷû ¶È°°ÀÌ µû¶óÇߴµ¥ ¾ÈµÇ¿ä ¤Ð¤Ð

Á¦°¡ /tmp ÆÄÀÏ¿¡¼­ level5.tmp¸¦ ¸¸µé¾ú´Âµ¥ ¾ÈµÇ´õ¶ó°í¿ä ¤Ð¤Ð
±×·¡¼­ ´Ù½Ã ¸¸µé¾î¼­ ls -al·Î ±ÇÇÑÀ» È®ÀÎ Çߴµ¥ ºÐ¸í level5 ±ÇÇÑÀ̰ɿ©Àִµ¥...

-rw-rw-r--    1 level5   level5          0  6¿ù  7 15:13 level5.tmp

±×·¡¼­ Àڽà ³×À̹ö ºí·Î±×¸¦ ºÃ´Âµ¥ level6°¡ Á¦°¡ ¸¸µç level5±ÇÇÑ ¶§¹®¿¡ level5.tmpÆÄÀÏÀ» »èÁ¦
¸øÇѴٴµ¥

¿Ö ¾î¶»°Ô ±×ÆÄÀÏÀ» »èÁ¦ÇßÀ»±î¿ä???

±×·¡¼­ /usr/bin/level5 ±ÇÇÑÀ» ºÃ´Âµ¥

-rwx--x---    1 level6   level5      14402  3¿ù 29  2003 /usr/bin/level5
¶ó°í ³ª¿Í Àִµ¥ ºí·Î±× »çÁø¿¡´Â /usr/bin/level5¿¡ level6 setuid°É¿©Àִµ¥....
Ȥ½Ã level6 setuid°¡ ¾È°É·Á¼­ ¾ÈµÇ´Â°É±î¿ä??


  Hit : 10499     Date : 2013/06/08 05:42



    
U_SoRang Á» Áú´ä °Ô½ÃÆÇ¿¡ ¿Ã¸³½Ã´Ù.
¿Ö ÀÚ²Ù Áú¹®À» ¿©±â¿¡´Ù ¿Ã¸®´Â °Ì´Ï±î.
2013/06/08  
benkim Á˼ÛÇÕ´Ï´Ù ¤Ð 2013/06/08  
whitetie level6 setuid°¡ ¾ø¾îµµ Ç® ¼ö ÀÖ´Â ¹®Á¦ÀÔ´Ï´Ù. 2013/06/09  
benkim ¾Æ °¨»çÇÕ´Ï´Ù ¤¾¤¾ 2013/06/09  
benkim Á¦°¡ ÇÁ·Î±×·¡¹Ö ÇØ¼­ Ç®¾ú½À´Ï´Ù ¤¾¤¾ 2013/06/09