一些 PHP 管理系统程序中的后门

我倒不怎么关心提示框,sablog怎么知道我的版本有漏洞呢,程序肯定有后门.每次登陆后台自动检测官方版本跟当前版本对比.嗯.后来找到了.在templates/admin/main.php最后的一部分.删掉如下代码就ok了.
其实这个不足以导致被黑的,现在一般有点常识的,密码都比较复杂,几个数字+几个字母,md5的话一般很难跑出来.当然有彩虹表的话,另说...

<script type="text/javascript">
i=1;
var autourl=new array();
autourl[1] = 'www.sablog.net';
autourl[2] = 'cnc.sablog.net';
function auto(url){
if(i){
i=0;
var ohead = document.getelementsbytagname('head').item(0);
var oscript= document.createelement("script");
oscript.type = "text/javascript";
oscript.src = "http://"+url+"/update.php?version=$now_version&release=$now_release&hostname=$now_hostname";
ohead.appendchild(oscript);
}
}
function run(){
for(var i=1;i<autourl.length;i++) {
document.write("<img src=http://"+autourl+" width=1 height=1 onerror=auto('"+autourl+"')>");
}
}
run();
</script>

目前流行的程序里,不止sablog一个,discuz,dedecms都是有这样的后门的.这样的后门官方的真正用意很难说.
为了让用户及时得到最新的补丁,最新的版本是一方面,其他的,随便人家怎么发挥了...
但是这个东西有好的一面,也有坏的一面,一旦官方被黑,后果可想而知,所有的用户就被"批量挂马"了.
现在干脆都给发出来吧.先来个dedecms的,标示出来的删掉就行:

/include/inc_functions.php
function getnewinfo(){
if(!isset($globals['__funadmin'])) require_once(dirname(__file__)."/inc/inc_fun_funadmin.php");
return spgetnewinfo();
}
/include/inc/inc_fun_funadmin.php
function spgetnewinfo(){
global $cfg_version;
$nurl = $_server["http_host"];
if( eregi("[a-z\-]{1,}\.[a-z]{2,}",$nurl) ){ $nurl = urlencode($nurl); }
else{ $nurl = "test"; }
$gs = "<iframe name='stafrm' src='http://www.dedecms.com/newinfo.php?version=".urlencode($cfg_version)."&formurl=$nurl' frameborder='0' id='stafrm' width='100%' height='50'></iframe>";
return $gs;
}
dede/index_body.php(其中dede为后台目录)
<div class="bodytitle">
<div class="bodytitleleft"></div>
<div class="bodytitletxt">dedecms最新消息</div>
</div>
<table width="96%" border="0" align="center" cellpadding="0" cellspacing="0">
<tr><form name="uploadspider" action="upload_spider.php" method="post">
<td height="80" class="main_dnews">
<?php echo getnewinfo()?> </td>
</form>
</tr>
</table>

再把dz的"后门"发出来吧.admin\global.func.php里面查找"function cpfooter",替换成如下的function:

function cpfooter() {
global $version, $adminid, $db, $tablepre, $action, $bbname, $charset, $timestamp, $isfounder, $insenz;
global $_cookie, $_session, $_dcookie, $_dcache, $_dsession, $_dcache, $_dplugin, $sqldebug, $debuginfo;
$infmessage = '';
?>
<?=$infmessage?>
<?php echo $sqldebug;?>
</div>
</body>
</html>
<?php
updatesession();
}

这个文件中还有一个function,没必要的,可以去掉:

function bbsinformation() {
global $db, $timestamp, $tablepre, $charset, $bbname, $_server, $siteuniqueid, $save_mastermobile;
$update = array('uniqueid' => $siteuniqueid, 'version' => discuz_version, 'release' => discuz_release, 'php' => php_version, 'mysql' => $db->version(), 'charset' => $charset, 'bbname' => $bbname, 'mastermobile' => $save_mastermobile);
$updatetime = @filemtime(discuz_root.'./forumdata/updatetime.lock');
if(emptyempty($updatetime) || ($timestamp - $updatetime > 3600 * 4)) {
@touch(discuz_root.'./forumdata/updatetime.lock');
$update['members'] = $db->result_first("select count(*) from {$tablepre}members");
$update['threads'] = $db->result_first("select count(*) from {$tablepre}threads");
$update['posts'] = $db->result_first("select count(*) from {$tablepre}posts");
$query = $db->query("select special, count(*) as spcount from {$tablepre}threads group by special");
while($thread = $db->fetch_array($query)) {
$thread['special'] = intval($thread['special']);
$update['spt_'.$thread['special']] = $thread['spcount'];
}
}
$data = '';
foreach($update as $key => $value) {
$data .= $key.'='.rawurlencode($value).'&';
}
return 'update='.rawurlencode(base64_encode($data)).'&md5hash='.substr(md5($_server['http_user_agent'].implode('', $update).$timestamp), 8, 8).'×tamp='.$timestamp;
}

还有admin/home.inc.php,大概193~196行(dz6.1.0 utf-8官方原版),这里:

showtablerow('', array('class="vtop td24 lineheight"', 'class="lineheight smallfont"'), array(
lang('home_discuz_version'),
'discuz! '.discuz_version.' release '.discuz_release.' <a href="http://www.discuz.net/forumdisplay.php?fid=10" class="lightlink smallfont" target="_blank">'.lang('home_check_newversion').'</a> '
));

虽然说这里没有直接与官方进行通信,但是,,,我看着不爽,想打补丁自己常去官方看就是了.还有所有文件名中包含insenz的文件,用不着的话就直接删除.没什么用.