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Daily AlpacaHack

A CTF challenge series with fun puzzles to enjoy every day

What is Daily AlpacaHack?

We regularly publish simple, beginner-friendly or educational CTF challenges!

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Solve each challenge within its time window to appear on the leaderboard.

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Today's Challenge
2501
The 3rd
Crypto
Hard
25 solves
Submissions (latest 3)
prof

SOLVED!

Sep 22, 3:03 PM

Leaderboard

Try the first challenge

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

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admin
AlpacaHack 2100
Misc
Welcome🌱
2,215 solves
Upcoming challenges reveal the , , and in advance.
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Sep 2026

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tchentchen
Springing
Web
Medium
74 solves
1
admin
QUIZ ALPACASHOCK
Misc
Welcome🌱
126 solves
2
hiikunzhiikunz
base 16-32-64
Misc
Easy🌱
102 solves
3-4
tan90909090tan90909090
Let's Shut Down Linux
Misc
Medium
63 solves
5
baumroll1234
6-8
minaminaominaminao
Bitflip RSA
Crypto
Hard
56 solves
 
minaminaominaminao
Bitflip RSA
Crypto
Hard
56 solves
9-11
minaminaominaminao
\^o^/
Misc
Hard
43 solves
12-13
tan90909090tan90909090
sin function vs. fsin instruction
Rev
Misc
Medium
55 solves
14-15
tan90909090tan90909090
integer division
Misc
Medium
70 solves
16-18
edwowmathedwowmath
neighboRhood_diStAnce
Crypto
Hard
41 solves
19-21
hiikunzhiikunz
nested eval
Misc
Hard
43 solves
 
hiikunzhiikunz
nested eval
Misc
Hard
43 solves
22-24
2501
The 3rd
Crypto
Hard
25 solves
25
Coming soon
26
Coming soon
27
Coming soon
28
Coming soon
29
Coming soon
30
Coming soon
1
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2
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3
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Writeups

Writeup for nested eval

baumroll1234

ja
nested eval

21 hours ago

Rows:

Decrypt Shop

Topic: RSAReleased: May 29, 2026

92 solves
Crypto
Medium5.0

by

pppp4649

pppp4649

Writeups

Writeup for Decrypt Shop

baumroll1234

ja

2026/05/29 18:20


Daily AlpacaHackに挑戦するつくよみちゃん 05/29/Decrypt Shop/pppp4649

ja

2026/05/30 06:59



nitcelcius

Writeup for Decrypt Shop (btw I don't like math)

ja

2026/05/29 15:36



kakur41

Writeup for Daily AlpacaHack 5/24-5/30

ja

2026/06/28 11:20


tadanobutubutu

Writeup for Decrypt Shop

ja

2026/05/29 17:16

descriptionsolveswriteups