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Challenges

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Rows:

CHALLENGEAUTHORS

SOLVES

(CURRENT)

SOLVE RATE

(AT CONTEST TIME)

AlpacaHack 2100
Misc

Daily AlpacaHack

admin

1633

solves

-

1544

solves

-

Daily AlpacaHack

883

solves

-

AlpacaHack Round 2 (Web)

611

solves

Top 28%

= 84/300 users

Daily AlpacaHack

594

solves

-

Daily AlpacaHack

567

solves

-

SECCON Beginners CTF 2024

505

solves

Top 73%

= 683/928 teams

Daily AlpacaHack

389

solves

-

Daily AlpacaHack

387

solves

-

echo
Pwn

AlpacaHack Round 1 (Pwn)

357

solves

Top 32%

= 56/174 users

Daily AlpacaHack

353

solves

-

Daily AlpacaHack

343

solves

-

Daily AlpacaHack

331

solves

-

Daily AlpacaHack

325

solves

-

Daily AlpacaHack

317

solves

-

Encoding Basics
Misc
Crypto

Daily AlpacaHack

317

solves

-

Daily AlpacaHack

312

solves

-

🐈
Web

Daily AlpacaHack

309

solves

-

Bars
Web

Daily AlpacaHack

299

solves

-

108
Misc

Daily AlpacaHack

296

solves

-

Rows:

a fact of CTF

Daily AlpacaHack
883 solves
Crypto

Author:

The very first challenge ever completed for AlpacaHack was never released because we adjusted the difficulty for the first Crypto round. (Organizers' note)

Beginner Hint
  • This challenge is in the Crypto (Cryptography) category.
  • AlpacaHack currently features four main categories: Crypto, Pwn, Rev, and Web; everything else goes into Misc.
  • Start by downloading the attached a-fact-of-CTF.tar.gz and extracting it.
  • In chall.py, the environment variable FLAG is read. This is the flag.
  • The flag is then transformed using prime numbers.
  • The output of chall.py is output.txt.
  • The goal is to recover the flag from the value in output.txt.
a-fact-of-CTF.tar.gz
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