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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

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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🌱
2,214 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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Writeups

Writeup for nested eval

baumroll1234

ja
nested eval

18 hours ago

Rows:

One Byte Padding Oracle Attack

Topic: Padding OracleReleased: Feb 26, 2026

81 solves
Crypto
Hard5.0

by

kurenaif

kurenaif

USER

SOLVED AT

haboro

2026/08/01 12:42

2026/07/20 05:15

2026/07/18 19:07

2026/07/03 02:40

2026/06/30 13:25

2026/04/29 15:08

2026/04/19 06:51

2026/04/01 07:11

2026/03/28 15:11

2026/03/28 04:32

2026/03/25 11:12

2026/03/24 10:27

2026/03/15 15:49

2026/03/07 09:35

2026/03/06 06:30

2026/02/28 11:44

2026/02/27 06:38

2026/02/27 04:29

2026/02/26 14:46

2026/02/26 14:33

2026/02/26 14:12

2026/02/26 14:12

2026/02/26 14:05

2026/02/26 13:48

2026/02/26 13:28

Rows:

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