real checkin xor

一个简单的异或

exp

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enc = [7, 31, 56, 25, 23, 15, 91, 21, 49, 15, 33, 88, 26, 48, 60, 58, 4, 86, 36, 64, 23, 54, 63, 0, 54, 22, 6, 55, 59, 38, 108, 39, 45, 23, 102, 27, 11, 56, 32, 0, 82, 24]
key = 'ez_python_xor_reverse'
flag = ''.join([chr(enc[i] ^ ord(key[i % len(key)])) for i in range(len(enc))])
print(flag)
#begin{3z_PY7hoN_r3V3rSE_For_TH3_Be9inNEr!}

flag

begin{3z_PY7hoN_r3V3rSE_For_TH3_Be9inNEr!}

xor

搞清楚调用就比较简单了，把变量名修改一下更清晰
2024-02-14T221507
2024-02-14T221537
类似的操作，搞清楚后反着逆回去就行

exp

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enc = "`agh{^bvuwTooahlYocPtmyiijj|ek'p"
key1 = '63290794207715587679621386735000'
key2 = '41803873625901363092606632787947'
a = [ord(enc[i]) for i in range(16)]
b = [ord(enc[i]) for i in range(16, 32)]
key11 = [ord(key1[i]) for i in range(16)]
key11.append(0)
key12 = [ord(key1[i]) for i in range(16, 32)]
key12.append(0)
key21 = [ord(key2[i]) for i in range(16)]
key21.append(0)
key22 = [ord(key2[i]) for i in range(16, 32)]
key22.append(0)
print(a)
print(b)
print(key11)
print(key12)
print(key21)
print(key22)
for i in range(16):
    a[i] ^= key22[16-i]
    b[i] ^= key21[16-i]
for i in range(16):
    a[i] ^= key21[16-i]
    b[i] ^= key22[16-i]
for i in range(16):
    a[i] ^= key22[i]
    b[i] ^= key21[i]
for i in range(16):
    a[i] ^= key21[i]
    b[i] ^= key22[i]
for i in range(16):
    a[i] ^= key11[16-i]
    b[i] ^= key12[16-i]
for i in range(16):
    a[i] ^= key12[16-i]
    b[i] ^= key11[16-i]
for i in range(16):
    a[i] ^= key11[i]
    b[i] ^= key12[i]
for i in range(16):
    a[i] ^= key12[i]
    b[i] ^= key11[i]
flag = ''.join([chr(a[i]) for i in range(16)] + [chr(b[i]) for i in range(16)])
print(flag)
#flag{Virus_gonna_be_terminated!}

flag

begin{Virus_gonna_be_terminated!}

红白机

给出如下代码,有点像是汇编

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LDA #$01
LDX #$00
LDY #$FF
d:
LDA #$01
STA $200,X
INX
CPX #$ff
BNE d
LDX #$00
STA $2FF,X
e:
LDA #$01
STA $300,X
INX
CPX #$ff
BNE e
LDX #$00
STA $3FF,X
f:
LDA #$01
STA $400,X
INX
CPX #$ff
BNE f
LDX #$00
STA $4FF,X
g:
LDA #$01
STA $500,X
INX
CPX #$ff
BNE g
LDX #$00
STA $5FF,X
LDX #$01
LDA #$00
STA $200,X
INX
STA $200,X
LDX #$21
STA $200,X
LDX #$40
STA $200,X
INX
STA $200,X
INX
STA $200,X
INX
LDX #$61
STA $200,X
LDX #$81
STA $200,X
LDX #$04
STA $200,X
LDX #$24
STA $200,X
LDX #$44
STA $200,X
LDX #$64
STA $200,X
LDX #$84
STA $200,X
LDX #$46
STA $200,X
INX
STA $200,X
INX
STA $200,X
LDX #$66
STA $200,X
INX
INX
STA $200,X
LDX #$86
STA $200,X
INX
STA $200,X
INX
STA $200,X
INX
STA $200,X
LDX #$4B
STA $200,X
INX
STA $200,X
INX
STA $200,X
LDX #$6B
STA $200,X
INX
INX
STA $200,X
LDX #$8B
STA $200,X
INX
STA $200,X
INX
STA $200,X
LDX #$AD
STA $200,X
LDX #$CB
STA $200,X
INX
STA $200,X
INX
STA $200,X
LDX #$10
STA $200,X
INX
STA $200,X
LDX #$30
STA $200,X
LDX #$50
STA $200,X
LDX #$70
STA $200,X
LDX #$6F
STA $200,X
LDX #$90
STA $200,X
LDX #$B0
STA $200,X
LDX #$D0
STA $200,X
INX
STA $200,X
n:
LDX #$34
STA $200,X
LDX #$53
STA $200,X
INX
INX
STA $200,X
LDX #$73
STA $200,X
LDX #$93
STA $200,X
INX
STA $200,X
INX
STA $200,X
LDX #$B3
STA $200,X
INX
INX
STA $200,X
LDX #$D4
STA $200,X
LDX #$37
STA $200,X
INX
STA $200,X
INX
STA $200,X
LDX #$57
STA $200,X
LDX #$77
STA $200,X
INX 
STA $200,X
LDX #$99
STA $200,X
LDX #$B9
STA $200,X
LDX #$D7
STA $200,X
INX
STA $200,X
LDX #$DC
STA $200,X
LDX #$BB
STA $200,X
INX
INX
STA $200,X
LDX #$9B
STA $200,X
INX
INX
STA $200,X
LDX #$7B
STA $200,X
INX
INX
STA $200,X
LDX #$5B
STA $200,X
INX
INX
STA $200,X
LDX #$3C
STA $200,X
LDX #$00
STA $300,X
INX
STA $300,X
INX
STA $300,X
LDX #$22
STA $300,X
LDX #$42
STA $300,X
LDX #$41
STA $300,X
LDX #$61
STA $300,X
LDX #$60
STA $300,X
LDX #$80
STA $300,X
LDX #$A0
STA $300,X
INX
STA $300,X
INX
STA $300,X
INX
INX
STA $300,X
INX
STA $300,X
INX
STA $300,X
INX
INX
STA $300,X
INX
STA $300,X
INX
STA $300,X
INX
INX
STA $300,X
INX
STA $300,X
INX
STA $300,X
INX
INX
STA $300,X
INX
STA $300,X
INX
STA $300,X
INX
INX
STA $300,X
INX
STA $300,X
INX
STA $300,X
INX
INX
INX
STA $300,X
LDX #$08
STA $300,X
INX
STA $300,X
INX
STA $300,X
LDX #$29
STA $300,X
LDX #$49
STA $300,X
LDX #$69
STA $300,X
LDX #$89
STA $300,X
LDX #$10
STA $300,X
LDX #$30
STA $300,X
LDX #$50
STA $300,X
LDX #$70
STA $300,X
LDX #$90
STA $300,X
LDX #$14
STA $300,X
INX
STA $300,X
INX
STA $300,X
LDX #$34
STA $300,X
INX
INX
STA $300,X
LDX #$54
STA $300,X
INX
INX
STA $300,X
LDX #$74
STA $300,X
INX
INX
STA $300,X
LDX #$94
STA $300,X
INX
INX
STA $300,X
LDX #$18
STA $300,X
INX
INX
STA $300,X
LDX #$38
STA $300,X
INX
INX
STA $300,X
LDX #$58
STA $300,X
INX
INX
STA $300,X
LDX #$78
STA $300,X
INX
INX
STA $300,X
LDX #$98
STA $300,X
INX
INX
STA $300,X
LDX #$1C
STA $300,X
INX
STA $300,X
INX
STA $300,X
LDX #$3C
STA $300,X
LDX #$5C
STA $300,X
INX
STA $300,X
INX
STA $300,X
LDX #$7C
STA $300,X
LDX #$9C
STA $300,X
LDX #$BC
STA $300,X
INX
STA $300,X
INX
STA $300,X
LDX #$C0
STA $400,X
INX
STA $400,X
INX
STA $400,X
INX
INX
STA $400,X
INX
STA $400,X
INX
STA $400,X
INX
INX
STA $400,X
INX
STA $400,X
LDX #$A4
STA $400,X
INX
INX
STA $400,X
LDX #$84
STA $400,X
INX
INX
STA $400,X
LDX #$64
STA $400,X
INX
INX
STA $400,X
INX
INX
INX
STA $400,X
INX
STA $400,X
LDX #$08
STA $400,X
INX
STA $400,X
LDX #$29
STA $400,X
LDX #$49
STA $400,X
LDX #$89
STA $400,X
LDX #$A9
STA $400,X

这是一个6502汇编代码，可以用6502在线汇编器来运行
2024-02-14T222338

flag

begin{6502_I_Love_u}

俄语学习

直接看主函数，有一堆的控制流
2024-03-12T170115
是一堆俄语阅读理解，尝试通过调试跳过
先在第一个jz跳转下断点，调试，然后在第一个jz跳转地址右键 set ip
2024-03-12T171000
来到最后一个跳转，在正确跳转的位置也set ip
2024-03-12T171353
然后一直F8，有提示
2024-03-12T171532
输入完跳转到 sub_71AFAA 函数
F7进入看看，几个关键函数
2024-03-12T171950
2024-03-12T171917
2024-03-12T172054
input+byte_7AAEE8-112之后和密文直接比较密文是+i&[@Y:g8[&l$f8S8v$Y&e>{
我们去找找 byte_7AAEE8是什么
看一下交叉引用
2024-03-12T173000
是中间某道题用到的数据，为unk_798E68 - 114
2024-03-12T173219
把unk_798E68 dump出来，写脚本梭
2024-03-12T173504

exp

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source = [0xA7, 0xDF, 0xA7, 0xD6, 0xA7, 0xE9, 0xA7, 0xD6, 0xA7, 0xD4, 0xA7, 0xE0, 0xA7, 0xDF, 0xA7, 0xD6, 0xA7, 0xE9, 0xA7, 0xD6, 0xA7, 0xD4, 0xA7, 0xE0, 0xA7, 0xDF, 0xA7, 0xD6, 0xA7, 0xE9, 0xA7, 0xD6, 0xA7, 0xD4, 0xA7, 0xE0]
enc = '+i&[@Y:g8[&l$f8S8v$Y&e>{'
flag = ''.join([chr(ord(enc[i]) + 112 - (source[i] - 114))for i in range(len(enc))]) 
print(flag)
#flag{Russian_is_so_easy}

flag

begin{Russian_is_so_easy}

ezpython

python 3.8 打包的exe，先用pyinstxtractor 解包
2024-03-14T122659
uncompyle6 反编译ezpython.pyc

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# uncompyle6 version 3.9.0
# Python bytecode version base 3.8.0 (3413)
# Decompiled from: Python 3.9.11 (tags/v3.9.11:2de452f, Mar 16 2022, 14:33:45) [MSC v.1929 64 bit (AMD64)]
# Embedded file name: ezpython.py
from gmssl import sm4
from secret import key, enc
import base64

def pad_pkcs7(data):
    """PKCS#7填充"""
    padding_len = 16 - len(data) % 16
    padding = bytes([padding_len] * padding_len)
    return data + padding


def unpad_pkcs7(padded_data):
    """PKCS#7去填充"""
    padding_len = padded_data[-1]
    return padded_data[:-padding_len]


class SM4:

    def __init__(self):
        self.gmsm4 = sm4.CryptSM4()

    def encryptSM4(self, encrypt_key, value):
        gmsm4 = self.gmsm4
        gmsm4.set_key(encrypt_key.encode(), sm4.SM4_ENCRYPT)
        padded_value = pad_pkcs7(value.encode())
        encrypt_value = gmsm4.crypt_ecb(padded_value)
        return base64.b64encode(encrypt_value)


if __name__ == '__main__':
    print('请输入你的flag:')
    flag = input()
    sm4_instance = SM4()
    flag_1 = sm4_instance.encryptSM4(key, flag)
    if flag_1 != enc:
        print('flag错误!!')
    else:
        print('恭喜你获得flag😊😀')

可以看到是一个sm4加密，key和enc在secret里
去PYZ-00.pyz_extracted里反编译secret.pyc(python版本不对这里就会是空的)

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# Source Generated with Decompyle++
# File: secret.pyc (Python 3.8)

key = 'BeginCTFBeginCTF'
enc = b'JmjJEAJGMT6F9bmC+Vyxy8Z1lpfaJzdEX6BGG/qgqUjUpQaYSON1CnZyX9YXTEClSRYm7PFZtGxmJw6LPuw1ww=='

直接调用gmssl库解密，发现解不出来，可能是魔改了
看看PYZ-00.pyz_extracted\gmssl\sm4.pyc是不是被魔改了

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# uncompyle6 version 3.9.0
# Python bytecode version base 3.8.0 (3413)
# Decompiled from: Python 3.9.11 (tags/v3.9.11:2de452f, Mar 16 2022, 14:33:45) [MSC v.1929 64 bit (AMD64)]
# Embedded file name: gmssl\sm4.py
import copy
from .func import xor, rotl, get_uint32_be, put_uint32_be, bytes_to_list, list_to_bytes, pkcs7_padding, pkcs7_unpadding, zero_padding, zero_unpadding
SM4_BOXES_TABLE = [
 214,  144,  233,  254,  204,  225,  61,  183,  22,  182,  20,  194,  40,  251,  44, 
 5,  43,  103,  154,  118,  42,  190,  4,  195,  170,  68,  19,  38,  73,  134, 
 6,  153,  156,  66,  80,  244,  145,  239,  152,  122,  51,  84,  11,  67,  237, 
 207,  172,  98,  228,  179,  28,  169,  201,  8,  232,  149,  128,  223,  148,  250, 
 117,  143,  63,  166,  71,  7,  167,  252,  243,  115,  23,  186,  131,  89,  60, 
 25,  230,  133,  79,  168,  104,  107,  129,  178,  113,  100,  218,  139,  248,  235, 
 15,  75,  112,  86,  157,  53,  30,  36,  14,  94,  99,  88,  209,  162,  37, 
 34,  124,  59,  1,  33,  120,  135,  212,  0,  70,  87,  159,  211,  39,  82, 
 76,  54,  2,  231,  160,  196,  200,  158,  234,  191,  138,  210,  64,  199,  56, 
 181,  163,  247,  242,  206,  249,  97,  21,  161,  224,  174,  93,  164,  155,  52, 
 26,  85,  173,  147,  50,  48,  245,  140,  177,  227,  29,  246,  226,  46,  130, 
 102,  202,  96,  192,  41,  35,  171,  13,  83,  78,  111,  213,  219,  55,  69, 
 222,  253,  142,  47,  3,  255,  106,  114,  109,  108,  91,  81,  141,  27,  175, 
 146,  187,  221,  188,  127,  17,  217,  92,  65,  31,  16,  90,  216,  10,  193, 
 49,  136,  165,  205,  123,  189,  45,  116,  208,  18,  184,  229,  180,  176,  137, 
 105,  151,  74,  12,  150,  119,  126,  101,  185,  241,  9,  197,  110,  198,  132, 
 24,  240,  125,  236,  58,  220,  77,  32,  121,  238,  95,  62,  215,  203,  57, 
 72]
SM4_FK = [
 2746333894, 1453994832, 1736282519, 2993693404]
SM4_CK = [
 462357,  472066609,  943670861,  1415275113, 
 1886879365,  2358483617,  2830087869,  3301692121, 
 3773296373,  4228057617,  404694573,  876298825, 
 1347903077,  1819507329,  2291111581,  2762715833, 
 3234320085,  3705924337,  4177462797,  337322537, 
 808926789,  1280531041,  1752135293,  2223739545, 
 2695343797,  3166948049,  3638552301,  4110090761, 
 269950501,  741554753,  1213159005,  1684763257]
SM4_ENCRYPT = 0
SM4_DECRYPT = 1
PKCS7 = 0
ZERO = 1

class CryptSM4(object):

    def __init__(self, mode=SM4_ENCRYPT, padding_mode=PKCS7):
        self.sk = [0] * 32
        self.mode = mode
        self.padding_mode = padding_mode

    @classmethod
    def _round_key(cls, ka):
        b = [0, 0, 0, 0]
        a = put_uint32_be(ka)
        b[0] = SM4_BOXES_TABLE[a[0]]
        b[1] = SM4_BOXES_TABLE[a[1]]
        b[2] = SM4_BOXES_TABLE[a[2]]
        b[3] = SM4_BOXES_TABLE[a[3]]
        bb = get_uint32_be(b[0:4])
        rk = bb ^ rotl(bb, 13) ^ rotl(bb, 23)
        return rk

    @classmethod
    def _f(cls, x0, x1, x2, x3, rk):

        def _sm4_l_t(ka):
            b = [
             0, 0, 0, 0]
            a = put_uint32_be(ka)
            b[0] = SM4_BOXES_TABLE[a[0]]
            b[1] = SM4_BOXES_TABLE[a[1]]
            b[2] = SM4_BOXES_TABLE[a[2]]
            b[3] = SM4_BOXES_TABLE[a[3]]
            bb = get_uint32_be(b[0:4])
            c = bb ^ rotl(bb, 2) ^ rotl(bb, 10) ^ rotl(bb, 18) ^ rotl(bb, 24)
            return c

        return x0 ^ _sm4_l_t(x1 ^ x2 ^ x3 ^ rk)

    def set_key(self, key, mode):
        key = bytes_to_list(key)
        key = [k ^ 37 for k in key]
        MK = [0, 0, 0, 0]
        k = [0] * 36
        MK[0] = get_uint32_be(key[0:4])
        MK[1] = get_uint32_be(key[4:8])
        MK[2] = get_uint32_be(key[8:12])
        MK[3] = get_uint32_be(key[12:16])
        k[0:4] = xor(MK[0:4], SM4_FK[0:4])
        for i in range(32):
            k[i + 4] = k[i] ^ self._round_key(k[i + 1] ^ k[i + 2] ^ k[i + 3] ^ SM4_CK[i])
            self.sk[i] = k[i + 4]
        else:
            self.mode = mode
            if mode == SM4_DECRYPT:
                for idx in range(16):
                    t = self.sk[idx]
                    self.sk[idx] = self.sk[31 - idx]
                    self.sk[31 - idx] = t

    def one_round(self, sk, in_put):
        out_put = []
        ulbuf = [
         0] * 36
        ulbuf[0] = get_uint32_be(in_put[0:4])
        ulbuf[1] = get_uint32_be(in_put[4:8])
        ulbuf[2] = get_uint32_be(in_put[8:12])
        ulbuf[3] = get_uint32_be(in_put[12:16])
        for idx in range(32):
            ulbuf[idx + 4] = self._f(ulbuf[idx], ulbuf[idx + 1], ulbuf[idx + 2], ulbuf[idx + 3], sk[idx])
        else:
            out_put += put_uint32_be(ulbuf[35])
            out_put += put_uint32_be(ulbuf[34])
            out_put += put_uint32_be(ulbuf[33])
            out_put += put_uint32_be(ulbuf[32])
            return out_put

    def crypt_ecb(self, input_data):
        input_data = bytes_to_list(input_data)
        if self.mode == SM4_ENCRYPT:
            if self.padding_mode == PKCS7:
                input_data = pkcs7_padding(input_data)
            else:
                if self.padding_mode == ZERO:
                    input_data = zero_padding(input_data)
        else:
            length = len(input_data)
            i = 0
            output_data = []
            while True:
                if length > 0:
                    output_data += self.one_round(self.sk, input_data[i:i + 16])
                    i += 16
                    length -= 16

        if self.mode == SM4_DECRYPT:
            if self.padding_mode == PKCS7:
                return list_to_bytes(pkcs7_unpadding(output_data))
            if self.padding_mode == ZERO:
                return list_to_bytes(zero_unpadding(output_data))
        return list_to_bytes(output_data)

    def crypt_cbc(self, iv, input_data):
        i = 0
        output_data = []
        tmp_input = [0] * 16
        iv = bytes_to_list(iv)
        if self.mode == SM4_ENCRYPT:
            input_data = pkcs7_padding(bytes_to_list(input_data))
            length = len(input_data)
            while True:
                if length > 0:
                    tmp_input[0:16] = xor(input_data[i:i + 16], iv[0:16])
                    output_data += self.one_round(self.sk, tmp_input[0:16])
                    iv = copy.deepcopy(output_data[i:i + 16])
                    i += 16
                    length -= 16

        else:
            return list_to_bytes(output_data)
            length = len(input_data)
            while True:
                if length > 0:
                    output_data += self.one_round(self.sk, input_data[i:i + 16])
                    output_data[i:i + 16] = xor(output_data[i:i + 16], iv[0:16])
                    iv = copy.deepcopy(input_data[i:i + 16])
                    i += 16
                    length -= 16

        return list_to_bytes(pkcs7_unpadding(output_data))

可以发现是set_key函数被魔改了，多了一行异或
解密的时候加一下

exp

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from gmssl import sm4
import base64

def pad_pkcs7(data):
    """PKCS#7填充"""
    padding_len = 16 - len(data) % 16
    padding = bytes([padding_len] * padding_len)
    return data + padding


def unpad_pkcs7(padded_data):
    """PKCS#7去填充"""
    padding_len = padded_data[-1]
    return padded_data[:-padding_len]


class SM4:

    def __init__(self):
        self.gmsm4 = sm4.CryptSM4()

    def decryptSM4(self, decrypt_key, value):
        gmsm4 = self.gmsm4
        gmsm4.set_key(decrypt_key.encode(), sm4.SM4_DECRYPT)
        padded_value = pad_pkcs7(value)
        decrypt_value = gmsm4.crypt_ecb(padded_value)
        return decrypt_value.decode()
key1 = 'BeginCTFBeginCTF'
enc = b'JmjJEAJGMT6F9bmC+Vyxy8Z1lpfaJzdEX6BGG/qgqUjUpQaYSON1CnZyX9YXTEClSRYm7PFZtGxmJw6LPuw1ww=='
key = ''.join([chr(ord(i) ^ 37) for i in key1])
sm4_instance = SM4()
flag = sm4_instance.decryptSM4(key, base64.b64decode(enc))
print(flag)
#flag{Pay_M0re_@ttention_to_th3_key!!}

flag

begin{Pay_M0re_@ttention_to_th3_key!!}

stick game

js逆向，看看index.js
找一下关键字 score
2024-03-14T131651
找到可能是初始化的地方这个计算出来是0，直接改成1337427试试
2024-03-14T131721
随便玩一下就出flag
2024-03-14T131905

flag

begin{y0u_re4l1y_g07_1337427_6b910ec24c42f540f822ed6d6b5d5ee0}

superguesser

直接动调，定位到sub_401530这里有个字符串

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.text:000000000040155B mov     byte ptr [rbp-60h], 51h ; 'Q'
.text:000000000040155F mov     byte ptr [rbp-5Fh], 51h ; 'Q'
.text:0000000000401563 mov     byte ptr [rbp-5Eh], 52h ; 'R'
.text:0000000000401567 mov     byte ptr [rbp-5Dh], 5Fh ; '_'
.text:000000000040156B mov     byte ptr [rbp-5Ch], 59h ; 'Y'
.text:000000000040156F mov     byte ptr [rbp-5Bh], 43h ; 'C'
.text:0000000000401573 mov     byte ptr [rbp-5Ah], 5Dh ; ']'
.text:0000000000401577 mov     byte ptr [rbp-59h], 5Fh ; '_'
.text:000000000040157B mov     byte ptr [rbp-58h], 59h ; 'Y'
.text:000000000040157F mov     byte ptr [rbp-57h], 49h ; 'I'
.text:0000000000401583 mov     byte ptr [rbp-56h], 5Ah ; 'Z'
.text:0000000000401587 mov     byte ptr [rbp-55h], 59h ; 'Y'
.text:000000000040158B mov     byte ptr [rbp-54h], 56h ; 'V'
.text:000000000040158F mov     byte ptr [rbp-53h], 2Eh ; '.'
.text:0000000000401593 mov     byte ptr [rbp-52h], 26h ; '&'
.text:0000000000401597 mov     byte ptr [rbp-51h], 1Dh
.text:000000000040159B mov     byte ptr [rbp-50h], 2Ah ; '*'
.text:000000000040159F mov     byte ptr [rbp-4Fh], 37h ; '7'
.text:00000000004015A3 mov     byte ptr [rbp-4Eh], 1Ah
.text:00000000004015A7 mov     byte ptr [rbp-4Dh], 27h ; '''
.text:00000000004015AB mov     byte ptr [rbp-4Ch], 29h ; ')'
.text:00000000004015AF mov     byte ptr [rbp-4Bh], 17h
.text:00000000004015B3 mov     byte ptr [rbp-4Ah], 28h ; '('
.text:00000000004015B7 mov     byte ptr [rbp-49h], 24h ; '$'
.text:00000000004015BB mov     byte ptr [rbp-48h], 2Ah ; '*'
.text:00000000004015BF mov     byte ptr [rbp-47h], 38h ; '8'
.text:00000000004015C3 mov     byte ptr [rbp-46h], 25h ; '%'
.text:00000000004015C7 mov     byte ptr [rbp-45h], 21h ; '!'
.text:00000000004015CB mov     byte ptr [rbp-44h], 3Dh ; '='
.text:00000000004015CF mov     byte ptr [rbp-43h], 0Fh
.text:00000000004015D3 mov     byte ptr [rbp-42h], 32h ; '2'
.text:00000000004015D7 mov     byte ptr [rbp-41h], 3Ah ; ':'
.text:00000000004015DB mov     byte ptr [rbp-40h], 3Ch ; '<'
.text:00000000004015DF mov     byte ptr [rbp-3Fh], 3Dh ; '='
.text:00000000004015E3 mov     byte ptr [rbp-3Eh], 36h ; '6'
.text:00000000004015E7 mov     byte ptr [rbp-3Dh], 33h ; '3'
.text:00000000004015EB mov     byte ptr [rbp-3Ch], 2Ah ; '*'
.text:00000000004015EF mov     byte ptr [rbp-3Bh], 0

直接把这个字符串dump出来

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enc = [0x51, 0x51, 0x52, 0x5F, 0x59, 0x43, 0x5D, 0x5F, 0x59, 0x49, 0x5A, 0x59, 0x56, 0x2E, 0x26, 0x1D, 0x2A, 0x37, 0x1A, 0x27, 0x29, 0x17, 0x28, 0x24, 0x2A, 0x38, 0x25, 0x21, 0x3D, 0x0F, 0x32, 0x3A, 0x3C, 0x3D, 0x36, 0x33, 0x2A, 0]

既然题目叫superguesser，那就猜一下

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enc = [0x51, 0x51, 0x52, 0x5F, 0x59, 0x43, 0x5D, 0x5F, 0x59, 0x49, 0x5A, 0x59, 0x56, 0x2E, 0x26, 0x1D, 0x2A, 0x37, 0x1A, 0x27, 0x29, 0x17, 0x28, 0x24, 0x2A, 0x38, 0x25, 0x21, 0x3D, 0x0F, 0x32, 0x3A, 0x3C, 0x3D, 0x36, 0x33, 0x2A, 0]
print(0x51 ^ ord('b'),0x51 ^ ord('e'),0x52 ^ ord('g'),0x5F ^ ord('i'),0x59 ^ ord('n'),0x43 ^ ord('{'))
#51 52 53 54 55 56

应该就是异或(51+i)

exp

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enc = [0x51, 0x51, 0x52, 0x5F, 0x59, 0x43, 0x5D, 0x5F, 0x59, 0x49, 0x5A, 0x59, 0x56, 0x2E, 0x26, 0x1D, 0x2A, 0x37, 0x1A, 0x27, 0x29, 0x17, 0x28, 0x24, 0x2A, 0x38, 0x25, 0x21, 0x3D, 0x0F, 0x32, 0x3A, 0x3C, 0x3D, 0x36, 0x33, 0x2A]
print(0x51 ^ ord('b'),0x51 ^ ord('e'),0x52 ^ ord('g'),0x5F ^ ord('i'),0x59 ^ ord('n'),0x43 ^ ord('{'))
flag = ''.join([chr(enc[i] ^ 51 + i) for i in range(len(enc))])
print(flag)
#51 52 53 54 55 56
#begin{debugging_is_an_anathor_choice}

flag

begin{debugging_is_an_anathor_choice}