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.

Not a Competition

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.

Solve stats

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No solved challenges yet.

Today's Challenge

Submissions (latest 3)

stp

SOLVED!

Jul 21, 12:14 PM

cfba82eb

SOLVED!

Jul 21, 10:48 AM

htbru

SOLVED!

Jul 21, 9:24 AM

Leaderboard

Period

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.

Jul 2026

Solved

Unsolved

Upcoming

Mon

Tue

Wed

Thu

Fri

Sat

Sun

tchen

Nano Services

Web

Medium

87 solves

minaminao

Super Short System Exit

Misc

Medium

82 solves

admin

Alpaca Nation

Misc

Welcome🌱

229 solves

hiikunz

Flag is A+B

Crypto

Easy🌱

138 solves

tchen

Lucky Redirect

Web

Easy🌱

130 solves

hiikunz

Renda

Rev

Medium

107 solves

tchen

IP Blocked Secret

Web

Hard

64 solves

minaminao

duplicate entry

Misc

Easy🌱

134 solves

hiikunz

Lazy RSA

Crypto

Medium

101 solves

minaminao

Let's Poly1305!

Crypto

Medium

76 solves

shiragi

private method

Misc

Easy🌱

128 solves

hiikunz

secret-table-3

Web

Medium

82 solves

baumroll1234

A slight mistake

Pwn

Hard

69 solves

tan90909090

Compile time flag checker

Rev

Hard

56 solves

baumroll1234

Redirecting to Login Page

Web

Easy🌱

137 solves

tchen

You've Got Shlex

Misc

Medium

86 solves

minaminao

Let's Poly1305! 2

Crypto

Hard

64 solves

tchen

Beat the Alpaca Lord

Web

Medium

88 solves

pppp4649

biribiri

Crypto

Medium

85 solves

tchen

Greetings CGI

Web

Hard

68 solves

hiikunz

no win func

Pwn

Hard

68 solves

tchen

Alpaca Blog

Web

Easy🌱

95 solves

tan90909090

NOP Variant

Rev

Misc

Medium

50 solves

Coming soon

minaminao

Planned topicCache

Web

Hard

tchen

Planned topicPython

Web

Hard

Coming soon

admin

Planned topicWelcome

Misc

Welcome🌱

Coming soon

Want a harder challenge?

Go to B-SIDE

Writeups

Writeup for Alpaca Blog

baumroll1234

Alpaca Blog

14 hours ago

Writeup for no win func

ojun

no win func

2026/07/19 15:04

Writeup for You've Got Shlex (shlex only)

kurimochi

You've Got Shlex

2026/07/19 05:58

Writeup for Greetings CGI

baumroll1234

Greetings CGI

2026/07/18 23:23

Writeup for You've Got Shlex

nitcelcius

You've Got Shlex

2026/07/18 12:59

Writeup for Compile time flag checker

edwowmath

Compile time flag checker

2026/07/18 02:07

Writeup for biribiri

baumroll1234

biribiri

2026/07/17 21:38

Writeup for Beat the Alpaca Lord

baumroll1234

Beat the Alpaca Lord

2026/07/16 21:24

Writeup for You've Got Shlex

tchen

author

You've Got Shlex

2026/07/16 01:15

Writeup for IP Blocked Secret

tchen

author

IP Blocked Secret

2026/07/15 23:53

Rows:

Small N

Topic: RSAReleased: May 3, 2026

187 solves

Crypto

Easy🌱3.0

pppp4649

USER	SOLVED AT
ken1220	2026/07/14 10:45
htbru	2026/07/13 07:57
totpro	2026/07/09 08:43
nirvana	2026/07/07 08:35
paper	2026/07/07 01:54
kannrisha	2026/06/29 03:33
kurao	2026/06/26 02:55
tmatsuura	2026/06/25 06:10
minouse3	2026/06/22 21:50
heanuts	2026/06/22 19:41
sgwr	2026/06/19 10:50
pineapple	2026/06/19 04:02
yukkinyaci	2026/06/12 11:50
nyaru	2026/06/10 11:15
kindness	2026/06/08 18:26
idaji	2026/06/07 06:31
qwra	2026/06/05 05:49
rito	2026/06/03 21:00
rj45	2026/06/03 14:37
chobix-code	2026/06/03 09:52
cardgamer	2026/06/03 03:51
toto1010orange	2026/06/02 11:59
yanchon918s	2026/06/01 05:31
kyokyokyo	2026/05/31 16:39
fox-alpha	2026/05/31 07:05