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Crypto - NumberTheory

解题脚本:

from Crypto.Util.number import inverse, long_to_bytes
import math

# 已知数据
n = 1055318040944102362946870824758284112187881439733520264163925427624371039188408 \
    6124172619325393637064819568245261834319547171964939408699779313765351896673921 \
    2122830015579955183805636213883066694989610003565432493653164047938048521354525 \
    623612253955387430773546124647105772639376194421783783651686606080214099

c = 6838127295540107402282470465780599628759317234806902778570348919850980664834107 \
    2270122496170360873810753440165503811371596435126722398264389032410916586193140 \
    7892193671978412352275860434939944023297151164991809322828884753468552635819180 \
    4172060250409498531941883162873696671060909325234109062997554795436940

hint = 2254571296159459611390959493560831065109921631767708603680850435226778110947934 \
       4217351256511531313022761442319626824021777583111841778031801484228020974742627 \
       1227826513967791945116378179885000662888744992914390207196310600996050316737090 \
       9993999623381332223707455892508533158768182263124533763402827488427796661769534 \
       5555305431032890129908315902905016995081288548688468234726304576491890719692231 \
       3892044095742248895091717187372068779768743879411865275203496650858608

e = 65537

# 1. 计算 h_prime
h_prime = hint // 233

# 2. 选择底数 a
a = 2

# 3. 计算 a^h_prime mod n
pow_h_prime = pow(a, h_prime, n)

# 4. 计算 GCD 找到 p
p = math.gcd(pow_h_prime - 1, n)

# 5. 检查 p 是否有效
if 1 < p < n:
    print(f"找到 p: {p}")
    # 6. 计算 q
    q = n // p
    print(f"找到 q: {q}")

    # 7. 验证 p*q == n
    if p * q == n:
        print("验证 n = p * q 成功")
        # 8. 计算 phi
        phi = (p - 1) * (q - 1)

        # 9. 计算私钥 d
        try:
            d = inverse(e, phi)
            print(f"计算得到 d: {d}")

            # 10. 解密
            m = pow(c, d, n)
            print(f"解密得到 m: {m}")

            # 11. 转换回 flag
            flag = long_to_bytes(m)
            print(f"找到 Flag: {flag}")
        except ValueError:
            print("计算 d 出错（e 和 phi 可能不互素）")
    else:hexo
        print("验证 n = p * q 失败")
else:
    print(f"计算得到的 GCD ⽆效: {p}")
    print("⽆法分解 n，请检查计算或尝试其他底数 a")

flag{158f26cca09e89b08cbd234c1f9c98c0}

Web - 这⽹⻚怪怪的

抓包302跳转发现⼀个yunnuuu.php

审代码很容易得到:

payload：/yunnuuu.php?tmp2=php://filter/convert.base64-encode/resource=flaaaaaaag.php

POST：tmp1=289114a

1.png

base64解密得到flag：flag{0T5KkBqUSYtMPcj41AduLR8zZfHXsWwa}

Usb

usb流量⼯具梭了

flag{whoami && rm -rf /opt}