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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
6 solves
Submissions (latest 3)
kurgm
kurgm

SOLVED!

Sep 21, 3:52 PM

serioton

SOLVED!

Sep 21, 3:19 PM

Leaderboard

Try the first challenge

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

View challenge
admin
AlpacaHack 2100
Misc
Welcome🌱
2,211 solves
Upcoming challenges reveal the , , and in advance.
Prev

Sep 2026

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tchentchen
Springing
Web
Medium
74 solves
1
admin
QUIZ ALPACASHOCK
Misc
Welcome🌱
124 solves
2
hiikunzhiikunz
base 16-32-64
Misc
Easy🌱
101 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
69 solves
16-18
edwowmathedwowmath
neighboRhood_diStAnce
Crypto
Hard
40 solves
19-21
hiikunzhiikunz
nested eval
Misc
Hard
39 solves
 
hiikunzhiikunz
nested eval
Misc
Hard
39 solves
22-24
2501
The 3rd
Crypto
Hard
6 solves
25
Coming soon
26
Coming soon
27
Coming soon
28
Coming soon
29
Coming soon
30
Coming soon
1
Coming soon
2
Coming soon
3
Coming soon
4
Coming soon

Want a harder challenge?

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Writeups

shiragi

Writeup for nested eval

shiragi

ja
nested eval

1 hour ago

gattoartz

Writeup for Alpaca Bank

gattoartz

Writeup for Read Assembly

gattoartz

Writeup for hit-and-miss

gattoartz

Writeup for simpleoverflow

curetwinkle

Writeup for simple ROP(アセンブリ解説多め)

ja

2026/09/15 03:55

Rows:

I wanna be the Admin

Topic: AuthorizationReleased: Jan 13, 2026

381 solves
Web
Easy🌱2.5

by

tchen

tchen

USER

SOLVED AT

wocucumber

6 hours ago

2026/09/16 06:58

2026/09/12 14:30

2026/09/11 04:50

2026/09/10 07:53

2026/09/10 06:28

2026/09/09 08:09

2026/09/08 04:19

2026/09/07 12:45

2026/09/07 01:03

2026/09/06 18:24

2026/09/02 16:25

2026/08/30 01:56

2026/08/28 10:14

2026/08/28 05:56

2026/08/27 13:44

2026/08/27 10:47

2026/08/26 13:43

2026/08/24 09:04

2026/08/23 03:39

2026/08/20 17:52

2026/08/20 15:41

2026/08/18 03:28

2026/08/16 16:03

2026/08/15 20:16

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