BUU平台逆向刷题

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 2021/02/06   Share

pyre

code = ['\x1f', '\x12', '\x1d', '(', '0', '4', '\x01', '\x06', '\x14', '4', ',', '\x1b', 'U', '?', 'o', '6', '*', ':', '\x01', 'D', ';', '%', '\x13']
l = len(code)

for i in range(l - 1):
    i = l-2-i
    code[i] = chr(ord(code[i]) ^ ord(code[(i + 1)]))

def in_range(j):
    return 33<= j and j <= 125

for i in range(l):
    i = l-1-i
    tmp = ord(code[i])-i
    data = tmp if in_range(tmp) else tmp+128
    code[i] = chr(data)

print("".join(code))
#GWHT{Just_Re_1s_Ha66y!}

IgniteMe

enflag = [
  0x0D, 0x26, 0x49, 0x45, 0x2A, 0x17, 0x78, 0x44, 0x2B, 0x6C, 
  0x5D, 0x5E, 0x45, 0x12, 0x2F, 0x17, 0x2B, 0x44, 0x6F, 0x6E, 
  0x56, 0x09, 0x5F, 0x45, 0x47, 0x73, 0x26, 0x0A, 0x0D, 0x13, 
  0x17, 0x48, 0x42, 0x01, 0x40, 0x4D, 0x0C, 0x02, 0x69
]

v4 = 4; flag = ["" for i in range(len(enflag))]
for i in range(len(enflag)):
    j = len(enflag)-i-1
    data = enflag[j]^v4
    flag[j] = chr(data)
    v4 = data

print("".join(flag))
# R_y0u_H0t_3n0ugH_t0_1gn1t3@flare-on.com

SimpleRev


def encode(v1,v3):
    v5 = 0xA
    key = "adsfkndcls"
    return (v1 - 39 - ord(key[v3 % v5]) + 97) % 26 + 97;

def brute(v3):
    answer = "killshadow"
    for i in range(65,91):
        if encode(i,v3+10) == ord(answer[v3]): print(chr(i),end="")

for i in range(10):
    brute(i)
# KLDQCUDFZO

特殊的 BASE64

import string
import base64
my_base64table = "AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz0987654321/+"
std_base64table ="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
s = "mTyqm7wjODkrNLcWl0eqO8K8gc1BPk1GNLgUpI=="
s = s.translate(str.maketrans(my_base64table,std_base64table))
print(base64.b64decode(s))
# flag{Special_Base64_By_Lich}

刮开有奖

Author：James Hoi

原文链接：https://jameshoi.github.io/2021/02/06/buuctf/

发表日期：February 6th 2021, 4:03:01 pm

更新日期：July 10th 2021, 12:55:35 am

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CATALOG

1. pyre
2. IgniteMe
3. SimpleRev
4. 特殊的 BASE64
5. 刮开有奖

缺失模块。
1、请确保node版本大于6.2
2、在博客根目录（注意不是archer根目录）执行以下命令：
npm i hexo-generator-json-content --save
3、在根目录_config.yml里添加配置：

jsonContent:
  meta: false
  pages: false
  posts:
    title: true
    date: true
    path: true
    text: false
    raw: false
    content: false
    slug: false
    updated: false
    comments: false
    link: false
    permalink: false
    excerpt: false
    categories: true
    tags: true