Daily AlpacaHack

A daily CTF challenge with a fun new puzzle every day

What is Daily AlpacaHack?

We publish one simple, beginner-friendly or educational CTF challenge every day!

Join Anytime

Solve within 24 hours of release to appear on the leaderboard.

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Discussion with friends or AI is welcome (account sharing is prohibited).

Solution Sharing Rules

Sharing solutions is allowed only after 24 hours have passed since release.

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Today's Challenge

minaminao

Super Short System Exit

Misc

Medium

16 solves

Submissions (latest 3)

mak0tan

SOLVED!

Jun 29, 4:43 PM

mti

SOLVED!

Jun 29, 4:24 PM

a01sa01to

SOLVED!

Jun 29, 4:19 PM

Leaderboard

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Try the first challenge

Is this your first CTF? Let's begin by tackling the first challenge released on Daily AlpacaHack.

Upcoming challenges reveal the , , and in advance.

Jun 2026

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Mon

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admin

Half-Year Recap

Misc

Welcome🌱

256 solves

minaminao

Cache Me If You Can

Web

Easy🌱

217 solves

minaminao

vm1

Misc

Medium

104 solves

pppp4649

Small e

Crypto

Easy🌱

141 solves

minaminao

RPS GAME

Misc

Crypto

Medium

101 solves

nozokare

Flag for localhost

Web

Easy🌱

180 solves

tan90909090

C++ flag checker

Rev

Hard

89 solves

shiragi

Guess IP

Misc

Easy🌱

150 solves

nozokare

A Piece of DHKE

Crypto

Medium

84 solves

shiragi

chmod-swapper

Misc

Medium

87 solves

tchen

Alpaca Certification

Web

Easy🌱

167 solves

rsk0315

Floating Equality

Misc

Medium

94 solves

pppp4649

Elliptic Equation

Crypto

Hard

62 solves

tchen

CAuth

Web

Hard

72 solves

minaminao

SITE/2

Web

Easy🌱

127 solves

tan90909090

Xored PNG

Misc

Medium

89 solves

tchen

Looks like Alpacahack

Web

Medium

87 solves

shiragi

Catrunner 2

Misc

Medium

108 solves

minaminao

Flag Printer 20XX

Misc

Hard

64 solves

nozokare

xorshift521

Crypto

Hard

55 solves

k0080

what-is-my-size

Pwn

Hard

67 solves

minaminao

✌️✌️✌️

Crypto

Easy🌱

96 solves

tchen

Secret Renderer

Web

Medium

83 solves

kanon

honk the klaxon

Crypto

Medium

58 solves

colza

voyage

Misc

Easy🌱

96 solves

rsk0315

Decimal float 101.0

Misc

Medium

65 solves

bubu

Style Your Alpaca

Web

Hard

54 solves

pppp4649

Only forward

Pwn

Hard

56 solves

tchen

Nano Services

Web

Medium

53 solves

minaminao

Super Short System Exit

Misc

Medium

16 solves

admin

Planned topicWelcome

Misc

Welcome🌱

hiikunz

Planned topicMathematics

Crypto

Easy🌱

tchen

Planned topicGeneral

Web

Easy🌱

hiikunz

Planned topicJavaScript

Rev

Medium

Coming soon

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Writeups

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2 minutes ago

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Only forward

22 hours ago

Writeup for Only forward: 3 Solutions

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Only forward

2026/06/28 15:46

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2026/06/28 15:18

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Decimal float 101.0

2026/06/28 13:05

Writeup for Daily AlpacaHack 6/14-6/20

kakur41

SITE/2

2026/06/28 12:35

Writeup for Daily AlpacaHack 6/7-6/13

kakur41

C++ flag checker

2026/06/28 12:19

Writeup for Daily AlpacaHack 5/31-6/6

kakur41

Half-Year Recap

2026/06/28 11:59

Writeup for Daily AlpacaHack 5/24-5/30

kakur41

AlpacaForm

2026/06/28 11:20

Rows:

Super Short System Exit

Topic: PythonReleased: Jun 30, 2026

16 solves

Misc

Medium5.5

minaminao

Only 5 bytes!

super-short-system-exit.tar.gz

description solves