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Rows:

CHALLENGEAUTHORS

SOLVES

(CURRENT)

SOLVE RATE

(AT CONTEST TIME)

Welcome
Misc

admin

858

solves

-

AlpacaHack Round 2 (Web)

366

solves

Top 28%

= 84/300 users

echo
Pwn

AlpacaHack Round 1 (Pwn)

240

solves

Top 32%

= 56/174 users

qrime
Crypto

AlpacaHack Round 3 (Crypto)

177

solves

Top 38%

= 91/239 users

AlpacaHack Round 7 (Web)

172

solves

Top 15%

= 71/458 users

CakeCTF 2023

148

solves

Top 33%

= 246/729 teams

AlpacaHack Round 6 (Pwn)

138

solves

Top 28%

= 57/197 users

AlpacaHack Round 8 (Rev)

112

solves

Top 19%

= 61/316 users

RTACTF 2023 Spring

107

solves

-

AlpacaHack Round 6 (Pwn)

104

solves

Top 20%

= 41/197 users

AlpacaHack Round 4 (Rev)

91

solves

Top 15%

= 42/279 users

AlpacaHack Round 3 (Crypto)

87

solves

Top 17%

= 42/239 users

AlpacaHack Round 1 (Pwn)

86

solves

Top 15%

= 27/174 users

AlpacaHack Round 7 (Web)

83

solves

Top 9%

= 42/458 users

CaaS
Web

AlpacaHack Round 2 (Web)

63

solves

Top 4%

= 13/300 users

AlpacaHack Round 3 (Crypto)

59

solves

Top 12%

= 30/239 users

AlpacaHack Round 2 (Web)

58

solves

Top 3%

= 10/300 users

XOR-CBC
Crypto

RTACTF 2023 Spring

57

solves

-

AlpacaHack Round 10 (Pwn)

57

solves

Top 42%

= 40/95 users

RTACTF 2023 Spring

56

solves

-

Rows:

42

SECCON CTF 13 決勝観戦CTF
52 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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