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Challenges

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Rows:

CHALLENGEAUTHORS

SOLVES

(CURRENT)

SOLVE RATE

(AT CONTEST TIME)

AlpacaHack 2100
Misc

Daily AlpacaHack

admin

1646

solves

-

1546

solves

-

Daily AlpacaHack

883

solves

-

AlpacaHack Round 2 (Web)

612

solves

Top 28%

= 84/300 users

Daily AlpacaHack

597

solves

-

Daily AlpacaHack

569

solves

-

SECCON Beginners CTF 2024

510

solves

Top 73%

= 683/928 teams

Daily AlpacaHack

392

solves

-

Daily AlpacaHack

388

solves

-

echo
Pwn

AlpacaHack Round 1 (Pwn)

357

solves

Top 32%

= 56/174 users

Daily AlpacaHack

355

solves

-

Daily AlpacaHack

346

solves

-

Daily AlpacaHack

332

solves

-

Daily AlpacaHack

328

solves

-

Daily AlpacaHack

320

solves

-

Encoding Basics
Misc
Crypto

Daily AlpacaHack

318

solves

-

Daily AlpacaHack

314

solves

-

🐈
Web

Daily AlpacaHack

312

solves

-

Bars
Web

Daily AlpacaHack

301

solves

-

108
Misc

Daily AlpacaHack

296

solves

-

Rows:

42

SECCON CTF 13 決勝観戦CTF
57 solves
Crypto

Author:

出力からフラグを復元してください🐍

import os
from Crypto.Util.number import getPrime, bytes_to_long

x = bytes_to_long(os.getenv("FLAG").encode())
for _ in range(42):
    x *= getPrime(42)
print(x)

出力:

1147519914005635970823022779519580521609222940350823007699842537827644738629829657046897975782350987748029018405699017377382521676899556171556649128260865812262043303782475632488849236816194782530154901066736272457909268699844626557409460652217501658644287801649083260640392194864370700199619482572398308537257922259125395585581757757644945754520977388691814074631081409677094992839775104691433743609551833747629636402523522392312458111656977789142053773849669780021688811768524291886161405435708715493344047580746854894532523408006689911316576153711061177239836663374119954672786387
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